Academic literature on the topic 'Apple fruit size'

Soluble solids content (SSC) is a vital evaluation index for the internal quality of apples, and NIR spectroscopy is the preferred technique for predicting the SSC of apples. Due to the differences in fruits’ sizes, their SSC prediction models have poor robustness and low prediction accuracy, so it is important to eliminate the effects brought by the differences in fruit sizes to improve the accuracy of fruit sorting models. The NIR spectra of apples with different fruit sizes were collected by applying NIR spectroscopy online detection device, and after various preprocessing of the spectra, the partial least squares (PLS) models of apple SSC were established, respectively, and then the modeling set in the apple fruit size group of 75 mm–85 mm was used to predict the prediction set samples in the apple fruit size group of 65 mm–75 mm and 85 mm–95 mm, respectively. To better address the effects of apple size differences, data fusion techniques were used to perform an intermediate fusion of apple fruit diameter and spectra, firstly, the competitive adaptive reweighting algorithm (CARS) and the continuous projection algorithm (SPA) were used to select spectral variables and build their prediction models for apple SSC, respectively, and the results showed that the models built with 61 spectral variables selected by CARS had better performance, greatly reduced the amount of data involved in modeling, effectively simplified the model, and improved the stability of the model. The apple size variables were added to the wavelength variables selected by CARS, and the data were normalized to establish a PLS model of apple SSC with the normalized spectral and apple fruit diameter data, and the results showed that the size compensation model based on intermediate fusion had the best prediction performance, with the prediction set Rp of 0.886 for fruit diameter of 65 mm–75 mm, RMSEP of 0.536%, and its prediction set Rp was 0.913 and RMSEP was 0.497% for the fruit diameter of 85 mm–95 mm. Therefore, adding the fruit diameter variable to establish the size-compensated model of apple SSC can improve the prediction performance of the model.

In 2001 and 2002, we imposed a wide range of croploads (0-15 fruits/cm2 of TCA) on 4- and 5-year-old Honeycrisp/M.9 trees by manual hand thinning soon after bloom to define appropriate croploads that give adequate repeat bloom and also the best fruit quality. At harvest each year we evaluated fruit ripening and quality. Samples were stored for 5 months in air at 38 °F and 33 °F and evaluated for fruit firmness and storage disorders. Cropload was negatively correlated with tree growth, return bloom, fruit size, fruit red color, fruit sugar content, fruit starch content, fruit firmness, fruit acidity, fruit bitter pit, fruit senescent breakdown, fruit rot and fruit superficial scald, but was positively correlated with leaf blotch symptoms, fruit internal ethylene concentration at harvest, and fruit soggy breakdown. There was a strong effect of cropload on fruit size up to a cropload 7, beyond which there was only a small additional effect. Although there was considerable variation in return bloom, a relatively low cropload was required to obtain adequate return bloom. Fruit red color was reduced only slightly up to a cropload of 8 beyond which it was reduced dramatically. The reduced fruit color and sugar content at high croploads could indicate a delay in maturity of but, fruits from high croploads were also softer, had less starch and greater internal ethylene. It that excessive croploads advance maturity. Overall, croploads greater than 10 resulted in no bloom the next year, and poor fruit size, color and flavor, but these fruits tended to have the least storage disorders. Moderate croploads (7-8) resulted in disappointing return bloom and mediocre fruit quality. For optimum quality and annual cropping, relatively low croploads of 4-5 were necessary.

In three experiments, diameters of apples representing 7% to 30% of the fruit on a tree were measured at ≈60 days after full bloom. Using previously published regression equations, the early-season fruit diameter values were used to estimate apple fruit weight at harvest (FWH). At harvest, all fruit on sample trees were weighed and the distributions of estimated FWH for fruit measured early in the season were compared with distributions of the actual FWH for whole trees. Actual FWH was normally distributed for only one of the three experiments. Although the estimated mean FWH averaged for the 10 trees was within 9% of the actual mean FWH for all three experiments, the distribution of estimated FWH differed significantly from the actual distribution for all three experiments. All fruit were then assigned to appropriate commercial fruit sizes or box counts (number of fruit/19.05 kg). Fruit size tended to peak on the same four box counts for the estimated and actual populations, but the estimated populations had too few fruits in the small- and large-size box counts. Using early-season estimates of FWH, commercial apple growers and packers can predict fairly accurately the percentage of the crop that will fall into the peak box counts, but a more accurate early-season estimate of the fruit size distribution will likely require measuring 50% of the fruit on a tree.

Fruit development in apple cultivars varying in their ultimate fruit size was analyzed using cytology, flow cytometry (FCM), and semi-quantitative RT-PCR. Fruit size variation across cultivars was largely explained by variation in cell number. The cell division phase lasted for less than 30 days in all varieties, less than previously believed. A distinct overlap between the cell division and cell expansion phases was present. Analysis of the relative cell production rate (rCPR) showed a major peak about 10 days after full bloom (DAFB) after which it declined. Comparison of the rCPR across varieties suggested distinct patterns of cell production with `Gala' having a low but sustained rCPR, `Pixy Crunch' a short but high rCPR, and `Golden Delicious' having a high and sustained rCPR. FCM analysis also showed similar patterns with a peak in the proportion of dividing cells about 10 DAFB followed by a decline. To further understand regulation of cell number, four cell cycle related genes were cloned from `Gala'. Cyclin Dependent Kinase B (CDK B) and Cyclin B were found to be highly cell division phase specific in their expression. Analysis of gene expression by semi-quantitative RT-PCR indicated peak expression of these two genes at 5-10 DAFB, consistent with the peaks in rCPR and proportion of dividing cells. Comparison of gene expression across the varieties showed higher peak expression of the above genes in the larger-fruited `Golden Delicious' than in the smaller-fruited `Gala.' This study provides novel insight into the regulation of fruit development in apple and also suggests a role for the cell cycle genes in fruit size regulation.

Intensive sampling was used to characterize the size and leaf type for tufted apple bud moth, Platynota idaeusalis (Walker), egg mass deposition, and to determine the association and site of larval feeding on fruit and foliage in Pennsylvania apple orchards. Results suggest tufted apple bud moth prefer to oviposit on smaller leaves (<20 cm2), and egg mass size was 0.16 cm2 during first brood and 0.12 cm2 during second brood. Significantly more first and second brood egg masses were oviposited on leaves within nonfruiting spurs than on either vegetative shoots or fruiting spurs. Both larval broods were found in association with leaves only rather than leaves and fruit. Fruit injury due to larval feeding during both broods occurred more on the calyx (sepals) surface area than the side or stem surface areas of the fruit. In cultivar comparisons of fruit, more surface injury was located on the site of the fruit from ‘Stayman’ trees than for ‘Golden Delicious’ trees.

Effects of NAA at 5, 10, and 15 ppm, Accel at 50, 75, and 100 ppm, NAA at 7.5 ppm plus carbaryl at 600 ppm, and a nontreated control on fruit set, fruit size, length–diameter ratio, seed numbers per fruit, and total yield of fruit were evaluated during the 1994 season. All treatments were applied to 10-year-old `Empire'/M.9/MM.111 trees as dilute sprays at a rate of 935 liters·ha–1 with an airblast sprayer on 3 June. King fruit measured 9–11 mm in diameter at time of application. Fruit set (fruits per 100 blossom clusters) was reduced significantly by Accel at 50 ppm (17%) and by NAA plus carbaryl (26%) in comparison with the nontreated control. Total yield of fruit was increased by all treatments; however, fruit from trees treated with NAA plus carbaryl was significantly larger than that from all other treatments. Percentages of small fruit, <108 g, were reduced by all treatments. Percentage of fruit ≥ 153 g was increased significantly only by NAA plus carbaryl. Length–diameter ratios and numbers of fully developed seeds per fruit were not influenced significantly by treatments. NAA at rates of 5, 10, and 15 ppm, or Accel at 50, 75, or 100 ppm, were less effective than a combination of NAA at 7.5 ppm plus carbaryl at 600 ppm in reducing fruit set and in affecting fruit size or fruit size distribution.

Canopies of `Fuji' apple trees, grafted on M.9 rootstock, planted in 1998 on two orchard sites at 2.8 × 0.7 m and trained as super spindles, were subdivided in Spring 2003 into upper and lower parts. In each part, the number of fruits, yield per tree, external (fruit size classes, and fruit coloring), and internal (total sugar content, titratable acid content, and flesh firmness) fruit quality attributes were determined. The orchard site parameters affected growth, yield, and fruit quality in different ways. The less suitable orchard site had less growth, lower yield per tree, and a lower percentage of first class fruits, but most fruits had good color (86% in top and 75% in lower part of canopy). The favorable orchard site produced higher growth and yield, and a higher percentage of first class fruits, but fruits had poorer color. In the lower part of the canopy, fruits were of a good size, but had poor color. Fruits of the best quality were obtained from the top part of the tree.

Apple fruit size preferences are known to vary among consumer populations. Characteristic commercial fruit size varies among apple-growing regions within Canada for a given cultivar. Canadian consumer preferences for apple size are not well documented, nor is it known whether preferences vary among regions. In this study, 586 consumers from British Columbia, Ontario and Nova Scotia were asked to rate a series of apple sizes using the affective “Just Right” scale. Ideal fruit size was similar regardless of province or consumer gender. Age groups differed slightly in fruit size preference. The Just Right score was a linear function of fruit diameter for all groups. The fruit diameter considered ideal for dessert use ranged from 7.4 to 7.6 cm among the age groups. Key words: Malus × domestica Borkh., sensory evaluation, consumer preference

Fifty four trees in a block of `Sturdeespur' Delicious on M.106 rootstock were given soil applications of various combinations of boron and gypsum. Twenty 2.9 to 3.0 inch diameter fruit and 20 unsized randomly chosen fruit were separately weighed and analyzed for Ca, Mg, K, and B concentrations. The coefficient of variation among fruit weights was greater for unsized than sized samples. Analyses of variance showed similar treatment effects for the two sampling methods. However, by using both sized and unsized fruit, effects of treatment on fruit size, and effects of relationships between fruit size and fruit mineral concentration may be separated.

Poor and erratic fruit colour development in ‘Cripps Pink’ apple causes serious economic losses to the growers and/or exporters of Western Australia and other parts of the world. Many internal and external factors such as genetic, light, temperature, irrigation, application of chemicals and also soil and tree factors affect the biosynthesis of anthocyanins consequently fruit colour. Some of the past approaches followed to improve fruit skin colour resulted in limited outcomes. The aim of my research was to evaluate the effects of water saving strategies and newly developed plant bioregulators in improving fruit colour development without adversely affecting fruit size and quality of ‘Cripps Pink’ apple at harvest, following cold and controlled atmosphere (CA) storage. I also investigated the individual polyphenolics profiles, their identification and confirmation in the skin of this apple cultivar. Nine polyphenolic compounds (cyanidin 3-O-galactoside, chlorogenic acid, phloridzin, quercetin 3-O-rutinoside, quercetin 3-O-galactoside, quercetin 3-O-glucoside, quercetin 3-O-xyloside, quercetin 3-O-arabinoside and quercetin 3-O-rhamnoside) in the fruit skin of ‘Cripps Pink’ apple were identified, quantified and re-confirmed using high performance liquid chromatography-electrospray ionization mass spectrometry (HPLC-ESI-MS). Increased concentration of cyanidin 3-O-galactoside in ‘Cripps Pink’ apple skin coincided with the increase in total anthocyanins concentrations.Water saving strategies, regulated deficit irrigation (RDI) and withholding irrigation (WHI), have been carried out for two seasons (2005-06 and 2006-07, and 2006-07 and 2007-08, respectively) in a commercial apple orchard. The treatment (75% RDI applied for 72 days, commencing on 135 days after full bloom (DAFB) and WHI for 20 to 30 days, commencing on 135 and 145 DAFB) increased red skin colour, concentration of total anthocyanins and polyphenolic compounds such as cyanidin 3-O-galactoside and quercetin glycosides. These treatments also improved fruit firmness and soluble solids concentration (SSC) of ‘Cripps Pink’ apple at harvest without adversely affecting postharvest quality in cold and controlled atmosphere (CA) storage, and also saved the irrigation water. To the best of my knowledge, this may be the first report on the effects of water-deficit on accumulation of flavonoids and other phenolic compounds in red-skinned apple particularly ‘Cripps Pink’ cultivar and also its impact on postharvest storage performance in CA storage. Soil-plant water relations such as volumetric soil water content, stomatal conductance, leaf water potential and stem water potential was pronounced with the application of these water saving strategies applied in the middle of stage II of fruit development of ‘Cripps Pink’ apple. The sparse leaf abscission due to water-deficit has improved light penetration, consequently improved red skin colouration through increased accumulation of anthocyanins particularly cyanidin 3-O-galactoside. This highlighted the importance of water stress and light in regulating colour and biosynthesis of anthocyanins.Newly developed plant growth regulator, Prohexadione-calcium (ProCa) improved fruit colour development of this apple cultivar by manipulating the light interception into the tree canopy and onto the fruit through reduction of vegetative growth. The reduction of shoot length was pronounced with three spray applications of ProCa (500 mg∙L[superscript]-1) on 3, 33 and 63 DAFB or two sprays of ProCa (500 mg∙L[superscript]-1) on 2 and 32 DAFB in combination with summer pruning (SP). The above mentioned treatments increased concentration of anthocyanins, cyanidin 3-O-galactoside, and all individual quercetin glycosides (quercetin 3-O-rutinoside, quercetin 3-O-galactoside, quercetin 3-O-glucoside, quercetin 3-O-xyloside, quercetin 3-O-arabinoside and quercetin 3-O-rhamnoside) and also maintained other fruit quality attributes such as fruit firmness and SSC of this apple cultivar.Lysophophatidylethanolamine (LPE) spray, 125 mg∙L[superscript]-1 (at two and four weeks prior to anticipated commercial harvest) or 250 mg∙L[superscript]-1 (at four weeks before harvest) appeared to be promising in improving fruit colour development, accumulation of anthocyanins and polyphenolic compounds (cyanidin 3-O-galactoside, quercetin glycosides and also individual quercetin glycosides such as quercetin 3-O-xyloside, quercetin 3-O-arabinoside and quercetin 3-O-rhamnoside), and other fruit quality attributes of ‘Cripps Pink’ apple. However, the mode of action of LPE in improving red colour in apple skin is possibly associated with enhanced ethylene production.In conclusion, fruit colour development of ‘Cripps Pink’ apple can be improved by applications of water saving techniques in the middle of stage II of fruit development such as 75% RDI for 72 days commencing on 135 DAFB or WHI for 20 (135-155 DAFB) to 30 (145-175 DAFB) days, and also newly developed plant bioregulators such as ProCa (three spray applications of ProCa (500 mg∙L[superscript]-1) on 3, 33 and 63 DAFB or two sprays of ProCa (500 mg∙L[superscript]-1) on 2 and 32 DAFB in combination with SP) or LPE (two spray applications (125 mg∙L[superscript]-1) at two and four weeks prior to anticipated commercial harvest or single spray (250 mg∙L[superscript]-1) at four weeks before harvest) without adversely affecting other fruit quality attributes.

Thesis (MScAgric)--Stellenbosch University, 2000.
ENGLISH ABSTRACT: The effect of foliar application oftriadimenol (a triazole), Promalin'", or scoring branches on fruit set, fruit size and fruit quality of 'Royal Gala' apples were evaluated. Four treatments were tested, viz., (a) an unsprayed control, (b) triadimenol sprayed on 6 March 1997 (one month after harvest) and then every two weeks for 8 weeks until leaf drop, as well as at mouse ear and full bloom, (c) as treatment b, plus Promalin® two weeks after full bloom, and (d) Promalin® two weeks after full bloom. Four scoring treatments were tested, viz., (a) a control, (b) scoring at full bloom, (c) scoring two weeks after full bloom, and (d) scoring four weeks after full bloom. Promalin® application two weeks after full bloom improved fruit size without any detrimental effects on fruit quality. This application was in addition to the standard commercial applications of Promalin'" as part of the chemical thinning program. The possible negative effect of the G~+7 on return bloom was however not determined. The scoring treatments were not severe enough to influence growth and development significantly and should be investigated again in the future. The influence of bearing position on apple flower and subsequent fruit quality was evaluated. At full bloom in the 1997/98 season, ten flower clusters from the following bearing positions were collected and evaluated: (a) dorsal spurs, (b) ventral spurs, (c) terminal on bourse shoot, (d) terminal on long shoot, and (e) lateral on long shoots. The same bearing positions were used, one week after full bloom, for the 1998/99 season. The flowering pattern was monitored for both seasons and just prior to harvest in both seasons the length and diameter of the fruit were measured as well as the length of the bourse shoot that had developed from the same bud. Fruit thinning by hand was done in 1997 by thinning to the largest fruit per cluster, but no thinning was done in the 1998 season. The results obtained in the morphological analysis of the flower cluster of 'Royal Gala' were not very consistent. In general, the dorsal spurs appeared to be the better quality flowers and the "king" flower is believed to be the best quality flower in the cluster as far as the receptacle dimensions are concerned. When fruit were harvested, no fruit on long shoots, either in the terminal or lateral positions, were found. Even though the percentage of these positions were low at bloom, this indicates a low set potential and possibly poor flower quality of these bearing positions in 'Royal Gala'. The size of the fruit at harvest in 1998/99, did not correlate well with the parameters measured at bloom. The correlation coefficients between bourse shoot length and fruit size were significant, but relatively small. We found a positive correlation between developed seed number and fruit dimensions. Thinning and heading pruning cuts affect fruit size and yield of 'Royal Gala' apple trees. During the 1997 winter trees were pruned as follows: (a) control with no further pruning, (b) thinning cuts of only entire secondary branches (branches that were thicker than half of the trunk diameter were removed at the point of attachment to the trunk), (c) thinning cuts of secondary branches and tertiary fruiting units (positioned on branches), (d) thinning of spurs only, without removal of branches or fruiting units, and (e) thinning cuts of branches and tertiary fruiting units combined with heading back of fruiting units into the spurs leaving four bud on the fruiting units. Treatments (b) through (e), were conducted at light or heavy pruning intensities, i.e., by leaving 300 or 150 reproductive buds/tree, respectively. Pruning was followed up by hand thinning of fruitlets to one fruit per cluster. All pruning treatments increased fruit size, primarily because of a indirect fruit thinning effect except the combined thinning and heading treatments where a direct effect resulted in the largest apples without having a negative effect on yield. In winter 1998 trees were pruned as follows: (a) control with no further pruning, (b) heavy thinning of secondary branches and fruiting units leaving 250 reproductive buds/tree, (c) light thinning of secondary branches and fruiting units leaving 400 reproductive buds/tree, (d) heavy thinning of secondary branches and fruiting units combined with heading back into the spurs of the remaining fruiting units leaving 250 reproductive buds/tree, and (e) light thinning of secondary branches and fruiting units combined with heading back into the spurs of the remaining fruiting units leaving 400 reproductive buds/tree. In 1998/99 season the advantage of pruning on fruit size were not observed. Lastly, the effect of artificial extinction (removal) of flower clusters on fruit size and quality of 'Royal Gala' apples were evaluated. Individual branches were pruned as follows: (a) control, (b) 25 % removal of fruiting spurs, (c) 50 % removal of fruiting spurs, (d) 75 % removal of fruiting spurs to test for any possible enhancements of fruit size. No subsequent hand thinning of fruitlets was done. Thinning by artificial extinction methods of the fruit buds did not influence fruit size, colour, seed set or seed development. No significant differences were found between fruit number, but with 50% and 75% bud removal fewer fruit were counted. In these data the absence of any significant fruit size improvement may be due to the lack of subsequent hand thinning of fruitlets.
AFRIKAANSE OPSOMMING: Die effek van blaarbespuiting van triadimenol en Promalin® asook ringelering op vrugset, vruggrootte en vrugkwaliteit is geëvalueer. Vier behandelings is toegepas nl: (a) onbehandelde kontrole, (b) triadimenol op 6 Maart 1997 en dan elke twee weke tot en met blaarval asook met "muis oor" en volblom, (c) soos behandeling b, plus Promalin® twee weke na volblom, en (d) Promalin® twee weke na volblom. Vier ringelering behandelings is ook toegepas nl: (a) geen ringelering (kontrole), (b) tydens volblom, (c) twee weke na volblom, en (d) vier weke na volblom. Promalin® bespuiting twee weke na volblom verbeter vruggrootte sonder enige nadelige effekte op vrugkwaliteit. Dit moet ingedagte gehou word dat hierdie behandeling van Promalin® was addisioneel toegevoeg tot die standard kommersiele gebruik van Promalin® wat deel vorm van die chemiese uitdun program. Die moontlike negatiewe effek van GA4+7 op blominisiasie is nie bepaal nie. Die ringelering behandelings was nie straf genoeg nie en dit het nie die groei en ontwikkeling betekenisvol beïnvloed nie en sal in die toekoms weer geëvalueer moet word. Verder is die invloed van draposisies op die appel blomkwaliteit en die daaropvolgende vrugkwaliteit geëvalueer. Met vol blom in die 1997/98 seisoen is tien blom trosse van die volgende draposisies versamel en geëvalueer: (a) dorsale spore, (b) ventrale spore, (c) terminaal op beurslote, (d) terminaal op langlote, en (e) lateraalop langlote. Dieselfde draposisies is versamel, een week na volblom, vir die 1998/99 seisoen. Die blompatroon is gemonitor gedurende beide seisoene. Net voor oes is die vruglengte en - deursnee gemeet as ook die lengte van die beurslote wat van dieselfde knop ontwikkel het as die vrugte. Vruguitdinning met die hand tot die grootste vrug per tros was gedoen in die 1997/98 seisoen, maar nie in die 1998/99 seisoen nie. Die resultate wat gekry is met die morfologiese analise van die blom trosse was nie baie konsekwent nie. In die algemeen vertoon die dorsale spore die beste kwaliteit blomme en die "koning" blomme het die grootste blombodems. Met die oes van die vrugte is geen vrugte op lang lote, hetsy in die terminale of laterale posisies gevind nie. Al was die persentasie van die posisies laag met volblom dui dit op lae setpotensiaal en moontlik ook op 'n lae blom kwaliteit van hierdie draposisies vir 'Royal Gala" appels. Die grootte van die vrugte van die 1998/99 oes korreleer nie goed met die parameters wat tydens blom gemeet is nie. Ongelukkig is die vrugte vir die 1998/99 seisoen nie gedurende die na-blom staduim uitgedun nie, wat daartoe bygedra het dat dit moeilik is om afleidings te maak. Die korrelasiekoeffisient tussen die beurslootlengte en vruggrootte was betekenisvol maar redelik klein. 'n Positiewe korrelasie tussen die aantal goed ontwikkelde sade en vrugdimensie is gevind. Die effek van uitdun en terugsnysnitte op vruggrootte eh opbrengs van 'Royal Gala' is ook geëvalueer. Gedurende die 1997 winter is die bome op die volgende manier gesnoei: (a) geen snoei (kontrole), (b) uitdunsnitte van hele sekondêre takke (takke wat dikker was as die helfde van die stam se deursnee by die punt van aanhegting aan die stam), (c) uitdunsnitte van sekondêre takke en tersiêre vrugdraende takke, (d) uitdun van spore alleen sonder om enige takke te verwyder, en (e) uitdunsnitte van sekondêre takke en tersiêre vrugdraende takke gekombineerd met terugsnysnitte van vrugdraende takke in die spoor sisteem in tot net vier spore per tak oorbly. Vir behandelings (b) tot (e) was die behandelings opgedeel in 'n ligte en 'n strawwe uitduning van knoppe deur onderskeidelik uit te dun tot 300 en 150 reproduktiewe knoppelboom. Die snoei was opgevolg deur handuitdunning tot een vrug per tros. Alle snoeibehandelings verbeter vruggrootte, primêr as gevolg van 'n indirekte vruguitdunnings, effek behalwe die behandeling met uitdunsnitte van sekondere takke en tersiêre vrugdraende takke gekombineerd met terugsnysnitte van vrugdraende takke. In hierdie behandeling is daar 'n direkte effek op vruggrootte sonder om 'n negatiewe effek op die oes opbrengs te he. In die winter van 1998 is die bome soos volg gesnoei: (a) geen snoei (kontrole), (b) strawwe uitdun snitte van hele sekondêre takke en vrugdraende takke tot op 250 reproduktiewe knoppe/boom, (c) ligteuitdun snitte van hele sekondêre takke en vrugdraende takke tot op 400 reproduktiewe knoppe/boom, (d) strawwe uitdunsnitte van sekondêre takke en tersiêre vrugdraende takke gekombineerd met terugsnysnitte van vrugdraende takke tot in die spoorsisteem tot op 250 reproduktiewe knoppelboom, en (e) ligte uitdunsnitte van sekondêre takke en tersiêre vrugdraende takke gekombineerd met terugsnysnitte van vrugdraende takke tot in die spoorsisteem tot op 400 reproduktiewe knoppelboom. Geen handuitdunning is gedurende die' seisoen gedoen nie, In die 1998/99 seisoen is geen voordeel van snoei op vruggrootte waargeneem nie. Snoei moet dus opgevolg word deur handuitdunning van vruggies. Laastens is daar na die effek van kunsmatige uitdun van blomtrosse op vruggrootte van 'Royal Gala' appels gekyk. Individuele takke is soos volg gesnoei: (a) kontrole, (b) 25 % verwydering van spore, (c) 50 % verwydering van spore, en (d) 75 % verwydering van spore. Geen opvolg handuitdunning is gedoen nie. Die uitdun tegniek het nie die vruggrootte, - kleur of die hoeveelheid en ontwikkeling van saad beïnvloed nie. Met die 50 % en 75 % verwydering is daar soos verwag minder vrugte geoes. Die rede dat geen vruggrootte verbetering gevind is nie kan moontlik daaraan toegeskryf word dat geen opvolg handuitdunning toegepas is nie.

Abstract All commercial sweet cherry trees are either budded or grafted. This chapter deals with sweet cherry rootstocks. Rootstocks are used for several purposes: (i) ease for propagating and producing more trees of a superior cultivar; (ii) better adaptation to particular soil or site characteristics; and (iii) the potential improvement of production due to additional traits like precocious flowering, higher productivity, and greater or reduced scion vigor as appropriate. Unfortunately, no one rootstock can satisfy all the requirements for consistently producing high yields of large, firm fruit of premium quality. Growers are advised to consider carefully the effects of each specific scion-rootstock combination as a function of environmental and cultural practices when replanting an orchard. Selecting the proper rootstock depends not only on the management skills of the grower, but also on the scion cultivar, training system, and site climate and soil selected for the orchard. Dwarfing, semi-dwarfing and even semi-vigorous rootstocks have major economic advantages over full-size rootstocks. The development of these new, precocious rootstocks has been almost as significant to the sweet cherry industry as to the apple industry several decades ago. When compared to Mazzard, Colt and even Mahaleb, size-controlling rootstocks have allowed sweet cherry growers an opportunity to plant high density, pedestrian orchards that become profitable more quickly, are more readily protected with orchard covering systems, and promote greater labor efficiency, easier management, and a safer and more productive work environment.

Horticultural industries are increasingly crucial in providing livelihoods, food quality, profits, and economic growth. In many horticultural plants, extensive studies were conducted to study the roles of hormones, epigenetics, and genes in regulating the development of cell number, cell size, fruit size, fruit weight, and endo-reduplication primarily via a gene-mapping technique known as quantitative trait loci (QTL). In general, these plants encompassed those with full-genomes sequenced, such as the apple, tomato, strawberry, and bananas. However, apart from fully sequenced apple genomes, the genome sequences of many other plants, particularly highly profitable tropical fruits, such as mangoes, pineapples, durians, and coconuts are yet available. This chapter will describe the interplay of plant hormones in determining fruit cell number and cell size, which, in turn, affects the final fruit size in horticultural plants.

Fruit and vegetables market is getting highly selective and requiring their suppliers to distribute the fruits of high standards of quality and good appearance. So the growing need to supply quality fruits within a short period of time has given rise to development of Automated Grading of fresh market fruits. The objective of this chapter is to classify apples into three grades based on its attributes such as color, size and weight. Initially apple image database is created. Next each image is analyzed using image processing software where images are first preprocessed and useful features like color and size are extracted from the images. Fuzzy logic is used for classification. Color, size features are represented as a fuzzy variables which are used for classification. The apples of different classes are graded into three grades viz. Grade1, Grade2 and Grade3 on the basis of combination of parameters mentioned above.

Fruit and vegetables market is getting highly selective and requiring their suppliers to distribute the fruits of high standards of quality and good appearance. So the growing need to supply quality fruits within a short period of time has given rise to development of Automated Grading of fresh market fruits. The objective of this chapter is to classify apples into three grades based on its attributes such as color, size and weight. Initially apple image database is created. Next each image is analyzed using image processing software where images are first preprocessed and useful features like color and size are extracted from the images. Fuzzy logic is used for classification. Color, size features are represented as a fuzzy variables which are used for classification. The apples of different classes are graded into three grades viz. Grade1, Grade2 and Grade3 on the basis of combination of parameters mentioned above.

To ensure populations have sufficient, safe, and nutritious food requires a concerted effort that involves politics, economics, farming practices, and enhancement of crops to withstand abiotic and biotic pressures yet remain productive. Keeping pace with population size and stresses imposed by climate change make it critical for plant scientists to have access and the freedom to apply all the tools available for crop improvement. The advent of gene editing increased the options for achieving desired traits and has been shown to be effective across a broad range of species including those in the Solanaceae, which contains some of the most relied upon food crops, such as tomato and potato. Traits related to disease resistance, fruit and tuber quality have been modified and improved through the use of editing in tomato and potato. Application and effectiveness of different editing approaches based on CRISPR/Cas of solanaceous species are outlined in this chapter.

Mainland Portugal (37°–42°Nlatitude) is located in the transitional region between the subtropical anticyclone and the subpolar depression zones. In addition to latitude, its orography and the effect of the Atlantic Ocean are the major factors affecting the climate of the mainland Portugal. The highest altitudes vary from 1000 m to 1500 m, with the exception of the Serra da Estrela range, whose peak is just below 2000 m. The regions farthest from the Atlantic Ocean are around 220 km away. Portugal has a total area of 9.2 million ha, 41% of which is devoted to cropland. Although agricultural practices in some regions are still traditional and not competitive, they are slowly becoming more and more industrialized and employ about 20% of the active population, which includes employment in agricultural industries as well. The inclusion of Portugal to the European Community in 1986, on the one hand, provided financial resources, but, on the other hand, caused agricultural policy to become more dependent on community policies. Farm size has doubled since the 1970s with increased mechanization. Wine production is the most important agricultural activity, which contributes significantly to Portugal’s economy (GPPAA, 1999). Among fruit trees, apples and citrus fruit have the highest productions, about 250,000 tons and 230,000 tons per year, respectively. Olive trees produce about 40,000 tons of olive oil per year (GPPAA, 1999). Food grain production is relatively low and not enough for domestic use. This is mainly due to the prevailing climate. The Portuguese climate is classified as Mediterranean, with some variations depending on orography and latitude. The annual cycles of monthly mean precipitation and temperature (minimum and maximum) reveal that warm and dry summers are more pronounced in the southern regions. This type of climate presents several drawbacks to agriculture, the major one being insufficient rainfall during the summer or spring seasons (Pinto and Brandão, 2002). Most of the rainfall occurs during winter season, from November until March. The majority of soils in Portugal are badly drained and suffer from water logging during the rainy season. A significant decrease in spring precipitation has been observed for last two decades.

Apple has a tendency to bear huge amount of flowers or inflorescences. Plants have ability to eliminate excess number of fruitlets. Frequently fruit trees eliminate insufficient number of fruitlets to grow good quality fruits. Most processes related to yield self-regulation varies significantly between different apples varieties. Also meteorological conditions influenced flower buds differentiation and fruit growth during blooming and other development stages. The investigations were carried out in 2015 – 2016 at the Institute of Horticulture. The main aim was to evaluate yield self-regulation peculiarity in various apple varieties in different meteorological conditions. In our experiment we made fruit self – thinning evaluation of 15 different varieties. Meteorological conditions were varying. In 2015 there was lack of rainfall, while 2016 year was rainy. After each fruit-drop period the number of developed and undeveloped seeds were counted of self-sheded and normally growing fruits. Amount of developed seeds as auxins source is one of the most important factor for yield self-regulation. Varieties of apple which are blooming abundantly and eliminate high amount of fruitlets, grows fruits until maturity with stabile amount of developed seeds and produces permanent harvest annually, independently from meteorological conditions during vegetation. Such apple varieties need higher amount of developed seeds to inhibit abscission. Apple varieties tended to bloom abundantly and eliminate small amount of fruitlets depending on meteorological conditions. Demand of auxins to carry fruits depends on meteorological conditions therefore these apple-trees develop different amount of seeds, when weather conditions changes. We may presume, that different apple varieties need different amount of phytohormones or their ratio to hold fruitlets on the apple. Therefore apple trees with smaller amount of seeds in fruits grow more fruits to its normal size.

The fresh market apple industry currently relies on manual labor for all harvesting activities. The lack of mechanical harvesting technologies is a serious concern because of rising labor costs and increasingly uncertain labor availability. Researchers have been working for several decades to develop mechanical harvesters for tree fruit. The two fruit removal methods considered include mass mechanical harvesters and selective harvesting with robotics technology. Whereas mass mechanical harvesters have demonstrated unacceptable damage rates, robotic systems have been limited by insufficient speed and robustness. This paper describes the design and analysis of a novel underactuated end-effector fabricated for the robotic harvesting of tree fruit. The device has been optimized around a set of target tasks, the most critical being speed, low complexity, suitability for a highly variable field environment, and the replication of hand picking so as to minimize fruit damage. Development of the end-effector has been facilitated by a thorough study of the dynamic forces involved during the manual harvesting of apples. The end-effector produces a spherical power grasp with a normal force distribution and picking sequence replicating selected human patterns. An underactuated, tendon-driven device with compliant flexure joints has been adopted to improve system performance in the presence of position errors as well as enhance robustness to variable fruit size, shape, and orientation. The prototype end-effector also uses minimal sensors and incorporates open-loop control to reduce complexity and improve picking speed. This paper presents the theoretical analysis of the end-effector kinematics and discusses the selection of key geometric parameters. Experiments have been conducted to determine the normal forces developed during grasping of the apple. Results indicate that open-loop, feedforward control can be used to produce optimal normal force patterns.

Concepts for real-time grading of fruits and vegetables were developed, including multi-spectral imaging with structured illumination to detect and distinguish surface defects from concavities. Based on these concepts, a single-lane conveyor and inspection system were designed and evaluated. Image processing algorithms were developed to inspect and grade large quasi-spherical fruits (peaches and apples) and smaller dried fruits (dates). Adjusting defect pixel thresholds to achieve a 25% error rate on good apples, classification errors for bruise, crack, and cut classes were 51%, 42%, and 46%, respectively. Comparable results for bruise, scar, and cut peach clases were 48%, 22%, and 58%, respectively. Acquiring more than two images of each fruit and using more than six lines of structured illumination per fruit would reduce sorting errors. Doing so, potential sorting error rates for bruise, crack, and cut apple classes were estimated to be 38%, 38%, and 33%, respectively. Similarly, potential error rates for the bruitse, scar, and cut peach classes were 9%, 3%, and 30%, respectively. Date size classification results were good: 68% within one size class and 98% within two size classes. Date quality classification results were not adequate due to the problem of blistering. Improved features were discussed. The most significant contribution of this research was the on-going collaboration with producers and equipment manufacturers, and the resulting transfer of research ideas to expedite the commercial application of machine vision for postharvest inspection and grading of agricultural products.

Blue mold of apple caused by Penicilliumexpansumis a major postharvest disease. Selection for postharvest disease resistance in breeding programs has been ignored in favor of fruit quality traits such as size, color, taste, etc. The identification of postharvest disease resistance as a heritable trait would represent a significant accomplishment and has not been attempted in apple. Furthermore, insight into the biology of the pathogenicity of P. expansumin apple could provide new approaches to postharvest decay management. Hypothesis: Postharvest resistance of apple to P. expansumcan be mapped to specific genetic loci and significant quantitative-trait-loci (QTLs) can be identified that account for a major portion of the population variance. Susceptibility of apple fruit to P. expansumis dependent on the ability of the pathogen to produce LysM effectors that actively suppress primary and/or secondary resistance mechanisms in the fruit. Objectives: 1) Identify QTL(s) and molecular markers for blue mold resistance in GMAL4593 mapping population (‘Royal Gala’ X MalussieversiiPI613981), 2) Characterize the transcriptome of the host and pathogen (P. expansum) during the infection process 3) Determine the function of LysM genes in pathogenicity of P. expansum. Methods: A phenotypic evaluation of blue mold resistance in the GMAL4593 mapping population, conducted in several different years, will be used for QTL analysis (using MapQTL 6.0) to identify loci associated with blue mold resistance. Molecular markers will be developed for the resistance loci. Transcriptomic analysis by RNA-seq will be used to conduct a time course study of gene expression in resistant and susceptible apple GMAL4593 genotypes in response to P. expansum, as well as fungal responses to both genotypes. Candidate resistance genes identified in the transcriptomic study and or bioinformatic analysis will be positioned in the ‘Golden Delicious’ genome to identify markers that co-locate with the identified QTL(s). A functional analysis of LysM genes on pathogenicity will be conducted by eliminating or reducing the expression of individual effectors by heterologous recombination and silencing technologies. LysMeffector genes will also be expressed in a yeast expression system to study protein function. Expected Results: Identification of postharvest disease resistance QTLs and tightly-linked genetic markers. Increased knowledge of the role of effectors in blue mold pathogenic

The proposed project aims to enhance tree fruit identification and targeting for robotic harvesting through the selection of appropriate sensor technology, sensor fusion, and visual servo-control approaches. These technologies will be applicable for apple, orange and grapefruit harvest, although specific sensor wavelengths may vary. The primary challenges are fruit occlusion, light variability, peel color variation with maturity, range to target, and computational requirements of image processing algorithms. There are four major development tasks in original three-year proposed study. First, spectral characteristics in the VIS/NIR (0.4-1.0 micron) will be used in conjunction with thermal data to provide accurate and robust detection of fruit in the tree canopy. Hyper-spectral image pairs will be combined to provide automatic stereo matching for accurate 3D position. Secondly, VIS/NIR/FIR (0.4-15.0 micron) spectral sensor technology will be evaluated for potential in-field on-the-tree grading of surface defect, maturity and size for selective fruit harvest. Thirdly, new adaptive Lyapunov-basedHBVS (homography-based visual servo) methods to compensate for camera uncertainty, distortion effects, and provide range to target from a single camera will be developed, simulated, and implemented on a camera testbed to prove concept. HBVS methods coupled with imagespace navigation will be implemented to provide robust target tracking. And finally, harvesting test will be conducted on the developed technologies using the University of Florida harvesting manipulator test bed. During the course of the project it was determined that the second objective was overly ambitious for the project period and effort was directed toward the other objectives. The results reflect the synergistic efforts of the three principals. The USA team has focused on citrus based approaches while the Israeli counterpart has focused on apples. The USA team has improved visual servo control through the use of a statistical-based range estimate and homography. The results have been promising as long as the target is visible. In addition, the USA team has developed improved fruit detection algorithms that are robust under light variation and can localize fruit centers for partially occluded fruit. Additionally, algorithms have been developed to fuse thermal and visible spectrum image prior to segmentation in order to evaluate the potential improvements in fruit detection. Lastly, the USA team has developed a multispectral detection approach which demonstrated fruit detection levels above 90% of non-occluded fruit. The Israel team has focused on image registration and statistical based fruit detection with post-segmentation fusion. The results of all programs have shown significant progress with increased levels of fruit detection over prior art.

The original objectives of the study, as defined in the approved proposal, are: To characterize the relationship of CreA and LaeA in regulation of P T production To understand how PacC modulates P. expansumpathogenicity on apples To examine if other secondary metabolites are involved in virulence or P. expansumfitness To identify the signaling pathways leading to PAT synthesis Penicilliumexpansum, the causal agent of blue mould rot, is a critical health concern because of the production of the mycotoxinpatulin (PAT) in colonized apple fruit tissue. Although PAT is produced by many Penicilliumspecies, the factors activating its biosynthesis were not clear. This research focused on host and fungal mechanisms of activation of LaeA (the global regulator of secondary metabolism), PacC (the global pH modulator) and CreA (the global carbon catabolite regulator) on PAT synthesis with intention to establish P. expansumas the model system for understanding mycotoxin synthesis in fruits. The overall goal of this proposal is to identify critical host and pathogen factors that mechanistically modulate P. expansumgenes and pathways to control activation of PAT production and virulence in host. Several fungal factors have been correlated with disease development in apples, including the production of PAT, acidification of apple tissue by the fungus, sugar content and the global regulator of secondary metabolism and development, LaeA. An increase in sucrose molarity in the culture medium from 15 to 175 mM negatively regulated laeAexpression and PAT accumulation, but, conversely, increased creAexpression, leading to the hypothesis that CreA could be involved in P. expansumPAT biosynthesis and virulence, possibly through the negative regulation of LaeA. We found evidence for CreAtranscriptional regulation of laeA, but this was not correlated with PAT production either in vitro or in vivo, thus suggesting that CreA regulation of PAT is independent of LaeA. Our finding that sucrose, a key ingredient of apple fruit, regulates PAT synthesis, probably through suppression of laeAexpression, suggests a potential interaction between CreA and LaeA, which may offer control therapies for future study. We have also identified that in addition to PAT gene cluster, CreA regulates other secondary metabolite clusters, including citrinin, andrastin, roquefortine and communesins, during pathogenesis or during normal fungal growth. Following creation of P. expansumpacCknockout strain, we investigated the involvement of the global pH regulator PacC in fungal pathogenicity. We demonstrated that disruption of the pH signaling transcription factor PacC significantly decreased the virulence of P. expansumon deciduous fruits. This phenotype is associated with an impairment in fungal growth, decreased accumulation of gluconic acid and reduced synthesis of pectolytic enzymes. We showed that glucose oxidase- encoding gene, which is essential for gluconic acid production and acidification during fruit colonization, was significantly down regulated in the ΔPepacCmutant, suggesting that gox is PacC- responsive gene. We have provided evidence that deletion of goxgene in P. expansumled to a reduction in virulence toward apple fruits, further indicating that GOX is a virulence factor of P. expansum, and its expression is regulated by PacC. It is also clear from the present data that PacC in P. expansumis a key factor for the biosynthesis of secondary metabolites, such as PAT. On the basis of RNA-sequencing (RNA-seq) analysis and physiological experimentation, the P. expansumΔlaeA, ΔcreAand ΔpacCmutants were unable to successfully colonize apples for a multitude of potential mechanisms including, on the pathogen side, a decreased ability to produce proteolytic enzymes and to acidify the environment and impaired carbon/nitrogen metabolism and, on the host side, an increase in the oxidative defence pathways. Our study defines these global regulatory factors and their downstream signalling pathways as promising targets for the development of strategies to fight against this post-harvest pathogen.

Objectives: The original objectives of this project were to: 1) evaluate inducible promoters for the expression of recombinase in apple (USDA-ARS); 2) develop alternative selectable markers for use in apple to facilitate the positive selection of gene excision by recombinase (Cornell University); 3) compare the activity of three different recombinase systems (Cre/lox, FLP/FRT, and R/RS)in apple using a rapid transient assay (ARO); and 4) evaluate the use of recombinase systems in apple using the best promoters, selectable markers and recombinase systems identified in 1, 2 and 3 above (Collaboratively). Objective 2 was revised from the development alternative selectable markers, to the development of a marker-free selection system for apple. This change in approach was taken due to the inefficiency of the alternative markers initially evaluated in apple, phosphomannose-isomerase and 2-deoxyglucose-6-phosphate phosphatase, and the regulatory advantages of a marker-free system. Objective 3 was revised to focus primarily on the FLP/FRT recombinase system, due to the initial success obtained with this recombinase system. Based upon cooperation between researchers (see Achievements below), research to evaluate the use of the FLP recombinase system under light-inducible expression in apple was then conducted at the ARO (Objective 4). Background: Genomic research and genetic engineering have tremendous potential to enhance crop performance, improve food quality and increase farm profits. However, implementing the knowledge of genomics through genetically engineered fruit crops has many hurdles to be overcome before it can become a reality in the orchard. Among the most important hurdles are consumer concerns regarding the safety of transgenics and the impact this may have on marketing. The goal of this project was to develop plant transformation technologies to mitigate these concerns. Major achievements: Our results indicate activity of the FLP\FRTsite-specific recombination system for the first time in apple, and additionally, we show light- inducible activation of the recombinase in trees. Initial selection of apple transformation events is conducted under dark conditions, and tissue cultures are then moved to light conditions to promote marker excision and plant development. As trees are perennial and - cross-fertilization is not practical, the light-induced FLP-mediated recombination approach shown here provides an alternative to previously reported chemically induced recombinase approaches. In addition, a method was developed to transform apple without the use of herbicide or antibiotic resistance marker genes (marker free). Both light and chemically inducible promoters were developed to allow controlled gene expression in fruit crops. Implications: The research supported by this grant has demonstrated the feasibility of "marker excision" and "marker free" transformation technologies in apple. The use of these safer technologies for the genetic enhancement of apple varieties and rootstocks for various traits will serve to mitigate many of the consumer and environmental concerns facing the commercialization of these improved varieties.

The objective of this research project was to evaluate the involvement of antioxidant enzymes and genes in the resistance mechanism to postharvest superficial scald development using two primary systems: 1. Resistant and susceptible progenies of an apple cross between a scald resistant crab apple, ‘White Angel’ and a scald susceptible cultivar, ‘Rome Beauty’; 2. Heat-treatment of ‘Granny Smith’, which is known to reduce scald development in this cultivar. In 2002 we asked for, and received (October 14), permission to revise our initial objectives. The US side decided to expand their results to include further work using commercial cultivars. Also, both sides wanted to include an emphasis on the interaction between these antioxidant enzymes and the á-farnesene pathway, with the cooperation of a third party, Dr. Bruce Whitaker, USDA-ARS, Beltsville. Background: Superficial scald is a physiological storage disorder that causes damage to the skin of apple and pear fruit. It is currently controlled by use of an antioxidant, diphenylamine (DPA), applied postharvest by drenching or dips, but concern exists about such chemical usage especially as it also involves application of fungicides. As a result, there has been increased emphasis on understanding of the underlying mechanisms involved in disorder development. Our approach was to focus on the oxidative processes that occur during scald development, and specifically on using the two model systems described above to determine if the levels of specific antioxidants and/or antioxidant enzyme activities correlated with the presence/absence of scald. It was hoped that information about the role of antioxidant-defense mechanisms would lead to identification of candidate genes for future transgenic manipulation. Major conclusions, solutions, achievements: Collectively, our results highlight the complexity of superficial scald developmental processes. Studies involving comparisons of antioxidant enzyme activities in different crab apple selection, commercial cultivars, and in response to postharvest heat and 1-methylcyclopropene (1-MCP) treatments, show no simple direct relationships with antioxidant contents and susceptibility of fruit to scald development. However, a correlative relationship was found between POX activity or isoenzyme number and scald resistance in most of the studies. This relationship, if confirmed, could be exploited in breeding for scald resistance. In addition, our investigations with key genes in the á-farnesenebiosynthetic pathway, together with antioxidant processes, are being followed up by analysis of exposed and shaded sides of fruit of cultivars that show different degrees of scald control by 1-MCP. These data may further reveal productive areas for future research that will lead to long term control of the disorder. However, given the complexity of scald development, the greatest research need is the production of transgenic fruit with down-regulated genes involved in á- farnesene biosynthesis in order to test the currently popular hypothesis for scald development.

Original objectives and revisions – The original overall objective was to develop, test and validate a prototype yield mapping system for unit area to increase yield and profit for tree crops. Specific objectives were: (1) to develop a yield mapping system for a static situation, using hyperspectral and thermal imaging independently, (2) to integrate hyperspectral and thermal imaging for improved yield estimation by combining thermal images with hyperspectral images to improve fruit detection, and (3) to expand the system to a mobile platform for a stop-measure- and-go situation. There were no major revisions in the overall objective, however, several revisions were made on the specific objectives. The revised specific objectives were: (1) to develop a yield mapping system for a static situation, using color and thermal imaging independently, (2) to integrate color and thermal imaging for improved yield estimation by combining thermal images with color images to improve fruit detection, and (3) to expand the system to an autonomous mobile platform for a continuous-measure situation. Background, major conclusions, solutions and achievements -- Yield mapping is considered as an initial step for applying precision agriculture technologies. Although many yield mapping systems have been developed for agronomic crops, it remains a difficult task for mapping yield of tree crops. In this project, an autonomous immature fruit yield mapping system was developed. The system could detect and count the number of fruit at early growth stages of citrus fruit so that farmers could apply site-specific management based on the maps. There were two sub-systems, a navigation system and an imaging system. Robot Operating System (ROS) was the backbone for developing the navigation system using an unmanned ground vehicle (UGV). An inertial measurement unit (IMU), wheel encoders and a GPS were integrated using an extended Kalman filter to provide reliable and accurate localization information. A LiDAR was added to support simultaneous localization and mapping (SLAM) algorithms. The color camera on a Microsoft Kinect was used to detect citrus trees and a new machine vision algorithm was developed to enable autonomous navigations in the citrus grove. A multimodal imaging system, which consisted of two color cameras and a thermal camera, was carried by the vehicle for video acquisitions. A novel image registration method was developed for combining color and thermal images and matching fruit in both images which achieved pixel-level accuracy. A new Color- Thermal Combined Probability (CTCP) algorithm was created to effectively fuse information from the color and thermal images to classify potential image regions into fruit and non-fruit classes. Algorithms were also developed to integrate image registration, information fusion and fruit classification and detection into a single step for real-time processing. The imaging system achieved a precision rate of 95.5% and a recall rate of 90.4% on immature green citrus fruit detection which was a great improvement compared to previous studies. Implications – The development of the immature green fruit yield mapping system will help farmers make early decisions for planning operations and marketing so high yield and profit can be achieved.

Over the last decade there has been a dramatic shift in global agricultural practice. The increase in human population, especially in underdeveloped arid and semiarid regions of the world, poses unprecedented challenges to production of an adequate and economically feasible food supply to undernourished populations. Furthermore, the increased living standard in many industrial countries has created a strong demand for high-quality, out-of-season vegetables and fruits as well as for ornamentals such as cut and potted flowers and bedding plants. As a response to these imminent challenges and demands and because of a ban on methyl bromide fumigation of horticultural field soils, soilless greenhouse production systems are regaining increased worldwide attention. Though there is considerable recent empirical and theoretical research devoted to specific issues related to control and management of soilless culture production systems, a comprehensive approach that quantitatively considers all relevant physicochemical processes within the growth substrates is lacking. Moreover, it is common practice to treat soilless growth systems as static, ignoring dynamic changes of important physicochemical and hydraulic properties due to root and microbial growth that require adaptation of management practices throughout the growth period. To overcome these shortcomings, the objectives of this project were to apply thorough physicochemical characterization of commonly used greenhouse substrates in conjunction with state-of-the-art numerical modeling (HYDRUS-3D, PARSWMS) to not only optimize management practices (i.e., irrigation frequency and rates, fertigation, container size and geometry, etc.), but to also “engineer” optimal substrates by mixing organic (e.g., coconut coir) and inorganic (e.g., perlite, pumice, etc.) base substrates and modifying relevant parameters such as the particle (aggregate) size distribution. To evaluate the proposed approach under commercial production conditions, characterization and modeling efforts were accompanied by greenhouse experiments with tomatoes. The project not only yielded novel insights regarding favorable physicochemical properties of advanced greenhouse substrates, but also provided critically needed tools for control and management of containerized soilless production systems to provide a stress-free rhizosphere environment for optimal yields, while conserving valuable production resources. Numerical modeling results provided a more scientifically sound basis for the design of commercial greenhouse production trials and selection of adequate plant-specific substrates, thereby alleviating the risk of costly mistrials.

Seedless cultivars dominate the table grape industry. In these cultivars it is mandatory to apply gibberellin (GA) to stimulate berry development to a commercially acceptable size. These cultivars differ in their sensitivity to GA application, and it frequently results in adverse effects such as decreased bud fertility and increased fruit drop. Our long term goals are to (1) understand the molecular basis for the differential sensitivity and identify markers for selection of sensitive cultivars (2) to develop new strategies for targeted manipulation of the grape berry response to GA that will eliminate the need in GA application and the undesirable effects of GA on the vine, while maintaining its desirable effects on the berry. Both strategies are expected to reduce production cost and meet growing consumer demand for reduced use of chemicals. This approach relies on a comprehensive characterization of the central components in the GA signaling cascade in the berry. Several key components in the GA signaling pathway were identified in Arabidopsis and rice, including the GA receptors, GID1s, and a family of DELLA proteins that are the major negative regulators of the GA response. GA activates its response pathway by binding to GID1s, which then target DELLAs for degradation via interaction with SLY, a DELLA specific F-box protein. In grape, only one DELLA gene was characterized prior to this study, which plays a major role in inhibiting GA-promoted stem growth and GA-repressed floral induction but it does not regulate fruit growth. Therefore, we speculated that other DELLA family member(s) may control GA responses in berry, and their identification and manipulation may result in GA-independent berry growth. In the current study we isolated two additional VvDELLA family members, two VvGID1 genes and two VvSLY genes. Arabidopsis anti-AtRGA polyclonal antibodies recognized all three purified VvDELLA proteins, but its interaction with VvDELLA3 was weaker. Overexpression of the VvDELLAs, the VvGID1s, and the VvSLYs in the Arabidopsis mutants ga1-3/rga-24, gid1a-2/1c-2 and sly1-10, respectively, rescued the various mutant phenotypes. In vitro GAdependent physical interaction was shown between the VvDELLAs and the VvGID1s, and GAindependent interaction was shown between the VvDELLAs and VvSLYs. Interestingly, VvDELLA3 did not interact with VvGID1b. Together, the results indicate that the identified grape homologs serve as functional DELLA repressors, receptors and DELLA-interacting F-box proteins. Expression analyses revealed that (1) VvDELLA2 was expressed in all the analyzed tissues and was the most abundant (2) VvDELLA1 was low expressed in berries, confirming former study (3) Except in carpels and very young berries, VvDELLA3 levels were the lowest in most tissues. (4) Expression of both VvGID1s was detected in all the grape tissues, but VvGID1b transcript levels were significantly higher than VvGID1a. (5) In general, both VvDELLAs and VvGID1s transcripts levels increased as tissues aged. Unfertilized and recently fertilized carpels did not follow this trend, suggesting different regulatory mechanism of GA signaling in these stages. Characterization of the response to GA of various organs in three seedless cultivars revealed differential response of the berries and rachis. Interestingly, VvDELLA3 transcript levels in the GA-unresponsive berries of cv. Spring blush were significantly higher compared to their levels in the highly responsive berries of cv. Black finger. Assuming that VvDELLA2 and VvDELLA3 are regulating berry size, constructs carrying potential dominant mutations in each gene were created. Furthermore, constitutive silencing of these genes by mIR is underway, to reveal the effect of each gene on the berry phenotype.

Rapid detection of pathogens and hazardous elements in fresh fruits and vegetables after harvest requires the use of advanced sensor technology at each step in the farm-to-consumer or farm-to-processing sequence. Fourier-transform infrared (FTIR) spectroscopy and the complementary Raman spectroscopy, an advanced optical technique based on light scattering will be investigated for rapid and on-site assessment of produce safety. Paving the way toward the development of this innovative methodology, specific original objectives were to (1) identify and distinguish different serotypes of Escherichia coli, Listeria monocytogenes, Salmonella typhimurium, and Bacillus cereus by FTIR and Raman spectroscopy, (2) develop spectroscopic fingerprint patterns and detection methodology for fungi such as Aspergillus, Rhizopus, Fusarium, and Penicillium (3) to validate a universal spectroscopic procedure to detect foodborne pathogens and non-pathogens in food systems. The original objectives proposed were very ambitious hence modifications were necessary to fit with the funding. Elaborate experiments were conducted for sensitivity, additionally, testing a wide range of pathogens (more than selected list proposed) was also necessary to demonstrate the robustness of the instruments, most crucially, algorithms for differentiating a specific organism of interest in mixed cultures was conceptualized and validated, and finally neural network and chemometric models were tested on a variety of applications. Food systems tested were apple juice and buffer systems. Pathogens tested include Enterococcus faecium, Salmonella enteritidis, Salmonella typhimurium, Bacillus cereus, Yersinia enterocolitis, Shigella boydii, Staphylococus aureus, Serratiamarcescens, Pseudomonas vulgaris, Vibrio cholerae, Hafniaalvei, Enterobacter cloacae, Enterobacter aerogenes, E. coli (O103, O55, O121, O30 and O26), Aspergillus niger (NRRL 326) and Fusarium verticilliodes (NRRL 13586), Saccharomyces cerevisiae (ATCC 24859), Lactobacillus casei (ATCC 11443), Erwinia carotovora pv. carotovora and Clavibacter michiganense. Sensitivity of the FTIR detection was 103CFU/ml and a clear differentiation was obtained between the different organisms both at the species as well as at the strain level for the tested pathogens. A very crucial step in the direction of analyzing mixed cultures was taken. The vector based algorithm was able to identify a target pathogen of interest in a mixture of up to three organisms. Efforts will be made to extend this to 10-12 key pathogens. The experience gained was very helpful in laying the foundations for extracting the true fingerprint of a specific pathogen irrespective of the background substrate. This is very crucial especially when experimenting with solid samples as well as complex food matrices. Spectroscopic techniques, especially FTIR and Raman methods are being pursued by agencies such as DARPA and Department of Defense to combat homeland security. Through the BARD US-3296-02 feasibility grant, the foundations for detection, sample handling, and the needed algorithms and models were developed. Successive efforts will be made in transferring the methodology to fruit surfaces and to other complex food matrices which can be accomplished with creative sampling methods and experimentation. Even a marginal success in this direction will result in a very significant breakthrough because FTIR and Raman methods, in spite of their limitations are still one of most rapid and nondestructive methods available. Continued interest and efforts in improving the components as well as the refinement of the procedures is bound to result in a significant breakthrough in sensor technology for food safety and biosecurity.