Dissertations / Theses on the topic 'Sorghum – Planting'

A study was conducted at the Maricopa Agricultural Center to determine the influence of planting date on time to flowering of sorghum hybrids. Sorghum was planted on March 19, April 16, May 14, June 18, July 2, July 16, and July 30. A total of 17 sorghum hybrids varying in maturity groups from early to late were planted at each date. The number of days from planting to flowering was greatest at the March 19 planting date and decreased with each planting date thereafter. Growing degree days required to reach flowering likewise decrease as planting was delayed. In order to avoid the heat during pollination in the early part of the summer, early to medium maturity hybrids need to be planted in mid-March at Maricopa. July planting dates resulted in flowering occuring in late August and September.

3 pp. / Originally published: 2009
Production practices for grain sorghum are discussed including hybrid selection, planting date, seeding rate, row configuration, irrigation, fertilization, pest control, and harvesting. Grain sorghum (milo) is a warm season, annual grain crop. It is more resistant to salt, drought, and heat stress than most other crops. Nevertheless, highest yields are obtained when stresses are minimized. Revised 10/2016. Originally published 06/2009.

Doctor of Philosophy
Department of Agronomy
P.V. Vara Prasad
Sorghum [Sorghum bicolor (L.) Moench] is a relatively drought- and heat-tolerant cereal crop. Global demand and consumption of agricultural crops for food, feed, and fuel is increasing at a rapid pace. To satisfy the growing worldwide demand for grain, production practices must be well optimized and managed. The objectives of the present study were: to optimize sorghum production by determining the best management practices (planting date, row spacing, seeding rate, hybrid maturity) for growth and yield, to evaluate the agronomic responsiveness of grain sorghum genotypes to nitrogen (N) fertilizer and to develop a partial financial budget to N fertilizer application based on best management practices. In order to meet these objectives, field experiments were conducted in 2009, 2010 and 2011 at Manhattan, Belleville, Ottawa, Hutchinson, Hays, at KSU Experiment Stations and Salina, and Randolph at Private Farms. Results indicated that early planting date (late May) and narrow row spacing (25 cm) providing the most equidistant spacing, produced better plant growth, light interception, yield components (number of grains per panicle, 300-grain weight), and biological yield. Results indicated that with increasing N rate, there was a proportional increase in chlorophyll SPAD meter reading, leaf color scores and number of green leaves. There was a significant difference among hybrids for N uptake, NUE and grain yield. However, there was no effect of N and no interaction between N and hybrid on grain yield. Over all, the genotypes with high NUE also had higher grain yield. Economic analysis using partial budget indicated that all N levels had positive gross benefit greater than control at all locations. However, the response varied across locations. Our research has shown that sorghum responds to changing management practices and opportunities exist to increase grain yield by optimizing planting date, seeding rate, row spacing, N application and selection of genotypes.

The Fall Armyworm is a serious pest of many crops throughout most of the Western Hemisphere particularly those belonging to the family Gramineae. This pest is usually controlled by insecticides which, however, cause many health and environmental problems. Although a rich bank of sorgum germplasm occurs in Yemen, no effort has been made to identify the Yemeni cultivars which might express resistance to armyworm attack. There is very little information to show at what time of the growing season and at what planting stage the sorghum cultivars are most susceptible to armyworms. Therefore, eight Yemeni and two American sorghum cultivars were planted in Tucson, Arizona, during 1983 and 1984. The experimental design was a randomized complete block arranged in split-split plots with four replications. The main plots were the varieties, and subplots were two planting dates and two infestation times. The plants were artificially infested with laboratory reared, first instar larvae. Infestation consisted of five larvae per plant in 1983 and ten in 1984. Results demonstrate the 'IBB' and 'TURBA' received the least leaf damage and 'SGIRL-MR1' and 'ALBAIDA' received the most in 1983. However, during 1984, 'TURBA' and 'HAIDRAN' showed the greatest degree of resistance and 'SGIRL-MR1', 'AMRAN', 'ALMAHWIT', and 'ALBAIDA' the least.

Forage sorghum (FS) [Sorghum bicolor (L.) Moench] is a warm-season biomass crop with the potential to become a bioenergy feedstock. The objective of this study was to screen potential FS genotypes for increased chilling tolerance and biomass productivity. The experiments were conducted in Fargo and Hickson, ND, in 2017 and 2018. Seventy-two genotypes of FS were tested at 24, 12, and 10℃. The genotypes were ranked from high to low vigor index and 12 genotypes were planted on two seeding dates: early (10 May) and late (27 May). Field emergence index values were greater for the late-seeding compared with the early-seeding date. Stand establishment and seed mortality were affected by the seeding date. Biomass yield correlated with emergence index and normalized vegetative index. Some of the genotypes tested had increased chilling tolerance and biomass yield when seeded earlier than normal, and may be used for breeding chilling tolerance into FS.

Master of Science
Department of Agronomy
Scott A. Staggenborg
In Kansas, productivity of grain sorghum [Sorghum bicolor (L.) Moench] is affected by weather conditions at planting and during pollination. Planting date management and selection of hybrid maturity group can help to avoid severe environmental stresses during these sensitive stages. The hypothesis of the study was that late May planting improves grain sorghum yield, growth and development compared with late June planting. The objectives of this research were to investigate the influence of planting dates on growth, development, and yield of different grain sorghum hybrids, and to determine the optimal planting date and hybrid combination for maximum biomass and grains production. Three sorghum hybrids (early, medium , and late maturing) were planted in late May and late June without irrigation in Kansas at Manhattan/Ashland Bottom Research Station, and Hutchinson in 2010; and at Manhattan/North Farm and Hutchinson in 2011. Data on leaf area index, dry matter production, harvest index, yield and yield components were collected. Grain yield and yield components were influenced by planting date depending on environmental conditions. At Manhattan (2010), greater grain yield, number of heads per plant, harvest index, and leaf-area were obtained with late-June planting compared with late May planting, while at Hutchinson (2010) greater yield was obtained with late May planting for all hybrids. The yield component most affected at Hutchinson was the number of kernels panicle-1 and plant density. Late-May planting was favorable for late maturing hybrid (P84G62) in all locations. However, the yield of early maturing hybrid (DKS 28-05) and medium maturing hybrid (DKS 37-07) was less affected by delayed planting. The effects of planting dates on growth, development, and yield of grain sorghum hybrids were found to be variable among hybrid maturity groups and locations.

Master of Science
Department of Agronomy
Rob M. Aiken
Mary Beth Kirkham
Prior studies indicate clumped planting can increase grain sorghum yield up to 45% under water deficit conditions by reducing tiller number, increasing radiation use efficiency, and preserving soil water for grain fill. The objective of this study was to evaluate effects of planting geometry on sorghum grain yield. The field study was conducted in seven environments with two sorghum hybrids, four populations, and two planting geometries. Crop responses included leaf area index, yield, and components of yield. Delayed planting decreased yield by 39%, and a later maturing hybrid increased yield, relative to an early hybrid, by 11% under water sufficiency. Clumped planting increased the fraction of fertile culms (culms which formed panicles) from 5-14%. It reduced the number of culms m-2 by 12% under water limiting conditions (at one of two locations) but increased culms m-2 16% under water sufficiency. Seeds per panicle and seed weight generally compensated for differences in panicles m-2, which were related to different planting population densities. Although agronomic characteristics of hybrids varying in maturity have been widely studied, little information exists concerning their physiological differences. Therefore, the objective of the greenhouse study was to determine if stomatal resistance, leaf temperature, and leaf chlorophyll content differed between two DeKalb grain sorghum [Sorghum bicolor (L.) Moench] hybrids. They were DKS 36-16 and DKS 44-20, of medium-early and medium maturity, respectively, when grown under field conditions in Kansas. Seeds were planted in a greenhouse. Stomatal resistance and leaf temperature were measured 55 days after planting with a Decagon Devices (Pullman, WA) diffusion porometer, and chlorophyll content was measured 119 days after planting with a Konica Minolta (Osaka, Japan) SPAD chlorophyll meter. The two hybrids did not differ in stomatal resistance, leaf temperature, chlorophyll content, height, and dry weight. Their difference in maturity was not evident under the greenhouse conditions. Future work needs to show if hybrids of different maturities vary in physiological characteristics

Please read the abstract in the 00front part of this document Copyright 2004, University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria. Please cite as follows: Bayu, W 2004, Growth, development and yield responses of sorghum to water deficit stress, nitrogen fertilizer, organic fertilizer, and planting density, PhD thesis, University of Pretoria, Pretoria, viewed yymmdd < http://upetd.up.ac.za/thesis/available/etd-09202006-093510 / >
Thesis (PhD (Agronomy))--University of Pretoria, 2004.
Plant Production and Soil Science
unrestricted

Doctor of Philosophy
Department of Agronomy
Scott A. Staggenborg and Alan J. Schlegel
Previous work in the High Plains with alternative planting geometries of corn and grain sorghum has shown potential benefits in dryland production. Studies conducted in 2009-2011 at Tribune, KS evaluated five planting geometries in corn and grain sorghum: conventional, clump, cluster, plant-one skip-one (P1S1), and plant-two skip-two (P2S2). Geometries were evaluated at three plant densities in corn: 3.0, 4.0, and 5.1 plants m[superscript]-2. Every measured corn production characteristic was affected by planting geometry, seeding rate, or an interaction in at least one of the years. Corn planted in a P2S2 configuration produced the least above-ground biomass, kernels plant[superscript]-1, kernels ear row[superscript]-1, and the highest kernel weight. Conventionally planted corn minimized harvest index and maximized stover production. Alternative geometries produced similar harvest indices. Grain yield response to seeding rate varied by geometry and year. Responsiveness and contribution of yield components were affected by geometry. Yield and yield components, other than ears plant[superscript]-1, were the least responsive to seeding rate in a cluster geometry. Clump planting consistently maximized kernels plant[superscript]-1. Prolificacy was observed in the cluster treatment and barrenness in the skip-row treatments. Light interception at silking was highest for clump and conventional geometries and lowest for the skip-row treatments. Corn in a P2S2 configuration did not fully extract available soil water. Conventionally planted corn had the lowest levels of soil water at tassel-silk indicating early-season use which potentially affected kernel set. In the lowest yielding year, grain water use efficiency was highest for clump and P2S2. Across-years, grain yields were lower for corn planted in a P2S2 geometry. Across-years corn yields were maximized when planted in clump at low or intermediate plant density, conventional and P1S1 at low plant density, P1S1 at high density, or cluster at any density. Planting grain sorghum in a P1S1 or P2S2 configuration reduced total biomass, grain yield, water use efficiency for grain production (WUEg), and water use efficiency for biomass production (WUEb) compared to conventional, clump, or cluster geometries at the yield levels observed in this study. Total water use was unaffected by planting geometry although cumulative water use at flower / grain fill was higher for conventional, clump, and cluster than for skip-row configurations. Sorghum planted in a conventional geometry was always in the highest grouping of grain yields. Grain yields from sorghum in either a cluster or clump geometry were each in the top yield grouping two of three years. When evaluated across-years, sorghum planted in a clump, cluster, or conventional geometry resulted in similar levels of above-ground biomass, grain yield, WUEg, and WUEb. Clump or cluster planting appear to have substantially less downside in a high yielding year than skip-row configurations. A comparison of corn and sorghum reinforced the findings of others that the relative profitability of the crops is largely dependent on the environment for any given crop year. Relative differences in grain yield, WUEg, WUEb, and net returns varied by year. Net returns over the three year study were maximized by conventional, cluster, and clump planted sorghum as well as clump planted corn.

The relative responses of corn (Zea mays L.), pearl millet (Pennisetum glaucum L.) and sorghum (Sorghum bicolor L.) to water stress and planting dates effects were studied. Two hybrids each of corn and sorghum and two inbred lines of pearl millet were grown from two planting dates of mid-May and mid-July under wet and dry soil moisture conditions. Water stress reduced plant heights, seed volume weight (except within the May planting, water stress increased seed volume-weight for sorghum), seed weight, and forage yield with less effect than for grain yield. Mid-July planting reduced the number of days to anthesis and heights of pearl millet and sorghum plants while it did increase the height of corn plants. Mid-May planting appeared to increase seed volume-weight and seed weight. Crops yielded more when planted in May except for pearl millet which yielded better under dry conditions when planted in July.

Published Article
A study involving two incubation experiments and a germination experiment in sandy soil was conducted to determine the influence of Multiplied Effective Micro-organisms (M-EM) that were exposed to different levels of irradiation and temperature fluctuation as well as prolonged storage, on the germination and seedling vigour of maize, sorghum and sunflower. Irrespective of poor handling and/or prolonged storage of M-EM, seed treatment with M-EM improved germination under optimal conditions for all crops compared to the control. Increased planting depths and cold stress were used to create conditions where seed treatment with M-EM may improve germination and seedling growth. Seed treatment with M-EM significantly improved germination and seedling vigour of the stress-tolerant maize cultivar following cold stress. Similar improved seedling vigour results were observed for the stress-tolerant sunflower cultivar at increased planting depth. It was concluded that the beneficial influence of M-EM as a seed treatment was remarkable, even after exposure of M-EM to unfavourable environmental conditions and prolonged storage before application. Further research under field conditions and in different cultivation systems are required before the large scale application of M-EM as seed treatment can be recommended.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
O aumento da população mundial e a necessidade crescente de alimentos têm levado à procura de sistemas de cultivo de alta produtividade e sustentabilidade. A integração lavoura-pecuária preenche esses requisitos pois permite a produção de grãos, carnes e outros produtos de origem animal em uma mesma área, garantindo também, quando bem manejada, o equilíbrio e conservação do solo. Entretanto, diferentes espécies concomitantemente em uma mesma área podem prejudicar a produtividade. Por isso, o objetivo foi analisar qual a melhor opção técnica e econômica num sistema de integração lavoura-pecuária sob plantio direto, cultivado por dois anos com sorgo consorciado com forrageiras tropicais e/ou guandu-anão e sucedido por soja ou milho. O delineamento experimental foi de blocos ao acaso, com quatro repetições. Os tratamentos foram constituídos por modalidades de sorgo forrageiro consorciado com: 1) Urochloa brizantha cv. Marandu; 2) U. brizantha cv. Marandu e guandu-anão; 3) Megathyrsus maximus cv. Mombaça; 4) M. maximus cv. Mombaça e guandu-anão; 5) guandu-anão e 6) sorgo solteiro, colhidos para silagem no primeiro corte e na rebrota e sucedidos por soja ou milho. Para tanto foram determinados: os atributos físico-químicos do solo antes de cada ano agrícola e após a colheita dos grãos de soja ou milho; os componentes de produção do primeiro corte e rebrota dos consórcios de sorgo com gramíneas forrageiras e/ou guandu-anão; o acúmulo de macronutrientes nas plantas em consórcio; o crescimento das forrageiras para formação de pasto; a taxa de decomposição da palhada das forrageiras; os componentes de produção da soja e do milho; o acúmulo de macronutrientes nos grãos; os custos de produção dos três anos agrícolas e os respectivos índices de lucratividade. A forrageira M. maximus prejudicou a rebrota do sorgo e a produtividade do milho semeado em sucessão, resultando em prejuízos econômicos. Os consórcios com o sorgo aumentaram o teor de matéria orgânica do solo na camada de 10 a 20 cm em relação ao sorgo solteiro. O uso de uma leguminosa acelerou a decomposição da palhada da forrageira consorciada. O cultivo de várias espécies em uma mesma área resultou em maior microporosidade do solo e acidez potencial se comparado ao cultivo do sorgo solteiro. Houve menor interferência dos consórcios cultivados anteriormente na soja em relação ao milho na região do Cerrado.
FAPESP: 2015/06685-0

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The use of cover crops in no-till system behind new challenges for proper management of nitrogen fertilizer on crops in succession, especially the most demanding in this nutrient, such as corn. This study aimed to evaluate the nitrogen fertilization in corn in succession to cover crops in southwestern Goiás. The experiment was conducted at the Federal University of Goiás -Jataí. The treatments were constituted by a 5X4 factorial, five cover crops (Brachiaria grass (Urochloa ruziziensis) (Crotalaria spectabilis), sorghum consortium (Sorghum bicolor) with braquiária, sorghum intercropping with C. juncea and fallow) and four doses of N topdressing (0, 50, 100, 150 kg ha-1) with four replications, totaling 80 installments. The experimental design was a randomized block. The sorghum consortium with sunn hemp and pasture showed higher intake of dry matter for corn in succession. Crotalaria single or intercropped with forage sorghum provided the largest grain yield in succession. The corn in succession to cover crops was responsive to nitrogen levels in coverage.
O uso de plantas de cobertura no sistema de plantio direto trás novos desafios para um adequado manejo da adubação nitrogenada nas culturas em sucessão, especialmente as mais exigentes neste nutriente, como é o caso do milho. O presente trabalho teve como objetivo avaliar a adubação nitrogenada no milho em sucessão a plantas de cobertura no sudoeste goiano. O experimento foi desenvolvido na Universidade Federal de Goiás –Jataí. Os tratamentos foram constituídos por um fatorial 5X4, sendo cinco plantas de cobertura (capim braquiária (Urochloa ruziziensis), crotalária (Crotalaria spectabilis), consórcio de sorgo (Sorghum bicolor) com braquiária, consórcio de sorgo com crotalária e pousio) e quatro doses de N em cobertura (0; 50; 100; 150 kg ha-1) com quatro repetições, totalizando 80 parcelas. O delineamento experimental foi em blocos casualizados. O consorcio de sorgo com crotalária e braquiária proporcionaram maior aporte de matéria seca para o milho em sucessão. Crotalária solteira ou consorciada com sorgo forrageiro proporcionaram maior produtividade do milho em sucessão. O milho em sucessão a plantas de cobertura foi responsivo às doses de nitrogênio em cobertura.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
O Brasil é o quarto maior produtor de grãos ao nível mundial. Sua agricultura é baseada em cultivos de sequeiro, com duas safras por ano. As recorrentes secas observadas nos últimos anos têm colocado em risco a produção agrícola brasileira e consequentemente o abastecimento mundial por alimentos. A segunda safra geralmente é a mais afetada, por estar associada à maiores riscos climáticos, principalmente pela baixa pluviosidade. Nesse sentido, tecnologias que otimizem o uso da água podem potencializar a produtividade e, ou, reduzir os riscos de quebra de safra na agricultura. O uso de polímeros superabsorventes (PSA) vem sendo consolidado no setor florestal resultando em redução das irrigações de pegamento das mudas devido ao aumento da capacidade de armazenamento de água no solo. Entretanto, não há relatos sobre o uso do PSA em culturas anuais. Neste contexto, objetivou-se com este trabalho avaliar o potencial de uso de polímero superabsorvente (PSA) como revestimento de sementes de sorgo em condições de estresse hídrico. Para isso, realizaram-se três experimentos inéditos: Experimento 1 – Sementes de sorgo com e sem revestimento com PSA foram semeadas em bandejas e submetidas a três intervalos de irrigação para induzir estresse hídrico nas plântulas. Avaliou-se a porcentagem de emergência e o índice de velocidade de emergência e, aos 26 dias após a semeadura, foram avaliadas a altura de plântulas, número de folhas por planta, taxa de sobrevivência e massa de matéria seca da parte aérea e da raiz. Verificou-se que o uso de PSA no revestimento de sementes pode contribuir com o desenvolvimento inicial de plântulas de sorgo e aumentar a taxa de sobrevivência em condições de déficit hídrico limitante ao cultivo. Contudo, o revestimento das sementes com PSA resultou em menores percentual e índice de velocidade de emergência. Experimento 2 – Para simular as condições de campo foram semeadas em vasos sementes de sorgo com e sem revestimento com PSA e também a aplicação do PSA no sulco de plantio, a fim de avaliar o uso e o método de aplicação do PSA. Aos 30 dias após a semeadura avaliou-se o estande de plantas, número de folhas por planta, altura de plantas e massa de matéria seca das folhas, do colmo e da raiz. Houve benefício do PSA quando aplicado no sulco de plantio para o crescimento vegetativo de plantas de sorgo. Contudo, também se observou interferência negativa do PSA na emergência das plântulas de sorgo cujas sementes foram revestidas com PSA. Experimento 3 – O uso do PSA foi testado em condições de campo, no período da segunda safra. O plantio foi realizado com sementes com e sem revestimento com PSA e também aplicação de diferentes doses do PSA no sulco de plantio. Aos 109 dias após a semeadura avaliou-se o estande de plantas, a altura de plantas, o diâmetro do colmo e a massa de matéria seca das folhas, do colmo e da panícula. Devido à elevada precipitação na fase inicial do experimento, não foi possível comprovar o possível efeito benéfico dos PSA no cultivo do sorgo em condição de sequeiro. Porém, o PSA aplicado como revestimento de semente prejudicou a emergência das plântulas, a altura e a matéria seca total. Conclui-se que o PSA aplicado em sulco de plantio apresenta potencial para ser utilizado na agricultura de sequeiro. Por outro lado, o PSA aplicado como revestimento de sementes prejudica a emergência e o índice de velocidade de emergência das plântulas. Entretanto, por se tratar de um estudo pioneiro, sugere-se a necessidade de novos trabalhos para investigar a interação entre o PSA e a semente a fim de melhorar a taxa de germinação das sementes revestidas que parece ser um dos maiores gargalos no momento para validar o potencial de uso destes materiais nas culturas arvenses.
Brazil is the fourth largest producer of grains worldwide. Its agriculture is based on rainfed crops, with two crops per year. The recurrent droughts observed in recent years have placed at risk the Brazilian agricultural production and consequently the global supply of food. The second crop is usually the most affected, it is associated with higher climate risks, especially for low rainfall. In this sense, technologies that optimize the use of water can enhance productivity and or reduce crop failure risks in agriculture. The use of superabsorbent polymers (PSA) has been consolidated in forestry resulting in reduction of irrigation of seedlings estabeleciment due to increased water storage capacity of the soil. However, there are no reports on the use of PSA in annual crops. In this context, the aim of this work was to evaluate the superabsorbent polymer use potential (PSA) as sorghum seed coating in water stress conditions. For this, there were three unpublished experiments: Experiment 1 - sorghum seeds with and without coating with PSA were sown in trays and subjected to three intervals of irrigation to induce water stress in plants. We evaluated the emergence percentage and emergence speed index and the 26 days after sowing, were evaluated seedling height, number of leaves per plant, survival rate and dry weight of shoot and root. It has been found that the use of PSA in the seed coating may contribute to the initial development of sorghum seedlings and increase the survival rate limiting drought conditions for cultivation. However, the coating of seeds with PSA resulted in lower percentage and emergence speed index. Experiment 2 - To simulate field conditions were sown in sorghum seed pots with and without coating with PSA and also the application of the PSA in the furrow, in order to evaluate the use and method of application of PSA. At 30 days after sowing evaluated the plant stand, number of leaves per plant, plant height and dry mass of leaves, stem and root. There was benefit of PSA when applied at planting to vegetative growth of sorghum plants. However, there was also negative interference of PSA in the emergence of sorghum whose seeds were coated with PSA. Experiment 3 - The use of PSA has been tested in field conditions, during the second season. Trees were planted with seeds with and without coating with PSA and also applying different PSA doses at planting. To 109 days after sowing evaluated the plant stand, plant height, diameter of the stem and the dry weight of the leaves, stem and panicle. Due to heavy rainfall in the initial phase of the experiment, it was not possible to prove the possible beneficial effect of PSA in sorghum cultivation in rainfed condition. Nevertheless, the PSA applied as a seed coating damaged seedling emergence, height and total dry matter. It is concluded that the PSA applied in the furrow has the potential to be used in rainfed agriculture. On the other hand, the PSA applied as a seed coating impairs the emergence and seedling emergence rate index. However, because it is a pioneering study, it suggests the need for further work to investigate the interaction between the PSA and the seed in order to improve the germination rate of the coated seeds that seems to be one of the biggest bottlenecks in time to validate the potential use of these materials in arable crops.

L'absorption du calcium, du fer et du zinc de régimes camerounais a été déterminée chez le rat. Le régime comprend 70% d'un aliment de base (taro dans le régime TA igname D. Dumetorum dans le régime IDU ; plantain dans le régime PL ; sorgho dans le régime SO) ; 10% d'arachide ; 5% de farine de poisson; des feuilles vertes, de l'huile de palme et du sel. Les régimes expérimentaux sont comparés à un régime témoin, semi-synthétique équilibré (T). Les critères utilisés sont la croissance pondérale, la rétention apparente, les concentrations minérales des tissus (foie, fémur, rein, sérum). Tous les régimes expérimentaux sont pauvres en calcium (275 à 520 mg/100 g ms) et conduisent à une diminution des concentrations du calcium sérique et du fémur. Le régime PL, également pauvre en protéines (11%) et en zinc (9 ppm), avec un rapport molaire (ca) (phytate): (zn) élevé (278) entraine un ralentissement de la croissance, un bilan négatif en zinc et une diminution des concentrations en zinc du foie (21%; p(0,05) et du fémur (14% exprimé en log du zinc total du fémur; P(0,001). L'absorption apparente mesurée indique que ces régimes sont suffisamment riches en fer pour couvrir les besoins. La supplémentation en caséine du régime PL entraine une amélioration significative de tous les paramètres : la croissance pondérale (+62%; P(0,01); les quantités de zinc retenues (+96% ; P(0,01) ; les concentrations en zinc du foie et du fémur (+61%; P(0,001; et +10%; P(0,05 respectivement). L'addition ultérieure de zinc est sans effet.

Orientador: Luís Roberto Almeida Gabriel Filho
Coorientador: Renato Jaqueto Goes
Coorientadora: Camila Pires Cremasco Gabriel
Resumo: O Sistema Plantio Direto (SPD) tem como característica a ocupação permanente do terreno agrícola com culturas vegetais além da manutenção da palhada sob a superfície do solo. Entretanto, para eficácia do SPD, é necessário adotar culturas de coberturas adequadas com a região a ser implementado, levando-se em consideração fatores edafoclimáticos e tipos de solo, para que dessa forma, haja a formação e manutenção da palhada sobre a superfície do solo. O sorgo possui como principais características, à tolerância de período de seca, e alto volume de produção de matéria seca, importantes para adoção dos sistemas de sucessão de culturas. O milheto, além da alta resistência à períodos de estresse hídrico, possui alta concentração de produção de biomassa. A taxa de decomposição da cobertura vegetal é regulada pela relação Carbono e Nitrogênio (C/N) específico de cada cultura. Nesse contexto, o presente trabalho visou analisar com modelos matemáticos os efeitos do nitrogênio sobre as culturas, sorgo e milheto, com finalidade de posterior uso como coberturas vegetais, sob níveis diferentes de nitrogênio em relação às variáveis de produtividade de matéria seca, teor de Nitrogênio (N), Fósforo (P), Potássio (K), Cálcio (Ca), Magnésio (Mg), Enxofre (S) e Molibdênio (Mo) e acúmulo de N, P, K, Ca, Mg, S e Mo com elaboração do modelo fuzzy. Foi realizada a comparação entre os modelos fuzzy (gaussiano e triangular) e de regressão polinomial por meio de testes estatísticos de ajustes de modelos... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The Direct Planting System (DPS) has as a characteristic the permanent occupation of the agricultural land with plant crops besides the maintenance of the straw under the soil surface. However, for DPS efficacy, it is necessary to adopt adequate cover crops with the region to be implemented, taking into account edaphoclimatic factors and soil types, so that the formation and maintenance of the straw on the soil surface. Sorghum has as main characteristics, to the tolerance of drought period, and high volume of dry matter production, important for the adoption of crop succession systems. Millet, besides the high resistance to periods of water stress, has high concentration of biomass production. The rate of decomposition of the vegetal cover is regulated by the relation Carbon and Nitrogen (C/N) specific of each culture. In this context, the present work aimed to analyze with mathematical models the effects of nitrogen on crops, sorghum and millet, with the purpose of later use as plant cover, under different levels of nitrogen in relation to the variables of dry matter yield content, Nitrogen (N), Phosphorus (P), Potassium (K), Calcium (Ca), Magnesium (Mg), Sulfur (S) and Molybdenum (Mo) and accumulation of N, P, K, Ca, Mg, S and Mo with elaboration of the fuzzy model. The comparison between the fuzzy (gaussian and triangular) and polynomial regression models was carried out by means of statistical tests of model adjustments and determination of the coefficient of determinati... (Complete abstract click electronic access below)
Mestre

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A cultura da soja vem sendo intensamente cultivada, no sistema plantio direto (SPD), na região do Cerrado. O solo, de baixa fertilidade e elevada acidez, e as altas temperaturas favorecendo a decomposição do material vegetal na superfície do solo, tem limitado o estabelecimento do SPD nesta região. Sendo assim, é de grande interesse a busca de alternativas que viabilizam a correção do solo e o incremento da palhada na implantação do SPD. Neste contexto, o objetivo deste trabalho foi avaliar culturas de cobertura, tipos e doses de calcário aplicadas na superfície do solo na implantação do SPD e seus efeitos na cultura da soja e nos atributos químicos do solo. O experimento foi conduzido na Fazenda experimental da UNESP – Campus de Ilha Solteira, localizada no município de Selvíria, MS em um LATOSSOLO VERMELHO Distrófico irrigado por pivô central. A área anteriormente foi cultivada com soja no sistema convencional. O sorgo e o milheto foram dispostos em faixa no sentido longitudinal da área experimental para facilitar a semeadura, enquanto que os tipos de calcário (PRNT de 100% e PRNT de 82%) e as doses (0,0, 0,25, 0,5, 1,0 e 2,0 vezes a calculada para elevar o V% a 60) foram distribuídos inteiramente ao acaso no sentido transversal da área. Foram avaliados os parâmetros de massa seca da parte aérea e porcentagem de cobertura do solo proporcionada pelas culturas de cobertura, estado nutricional das plantas de soja, características agronômicas da soja e atributos químicos do solo. O sorgo produziu maior quantidade de massa seca proporcionando maior cobertura do solo, porém a palhada de milheto foi mais duradoura na superfície do solo. A soja cultivada em sucessão ao sorgo, apresentou menor crescimento vegetativo e redução no número de vagens e massa de 1000 sementes. A aplicação superficial do calcário com PRNT de 100% proporcionou aumento...
In Brazil, the soybean is intensively cropped under non-till system on the Cerrado region. However the low fertility and pH values of the soil, and high air temperature conditions increase the organic matter decomposition on the soil surface, limiting the non-till system establishment. In this way, searches for alternatives that promote a good soil correction with plant coverage enhancement for a non-till systems establishment are needed. The aim of this work was to evaluate the cover crops, types and levels of limestone during a non-till system establishment and its effects on soybean cropping and soil chemical characteristics. The experiment was carried out at experimental farm of the UNESP, district of Selvíria, Mato Grosso do Sul State in a distrofic red latosoil irrigated with a center pivot. Sorghum and millet were disposed in a longitudinal strip direction from the experimental area to facilitate the sowing while the limestone types (PRNT 100% and PRNT 82%) and the levels of input (0.0, 0.25, 0.5, 1.0 and 2.0 times the prescribed level to elevate the V% to 60) were randomly distributed in a transversal way. The shoot dry mass production, the percentage of soil coverage by crops cover, the nutritional and characteristics of soybean plants and the chemical attributes of soil were evaluated. Sorghum showed high values of shoot dry mass than millet, however, the millet dry mass was more enduring on soil surface. Soybean cropped in succession to sorghum shown an decrease in vegetative growth, number of pods and fresh mass of 1000 seeds. On the other hand, the superficial liming with PRNT 100% provided an increase in the number of pods and consequently increases on yield of soybeans. Independently of granulometry the increase in levels of inputted limestone was directly proportional to decreasing on contents of Fe, Zn and Mn ions of soybean leaf tissues... (Complete abstract, click electronic access below)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
A escolha de espécies a serem utilizadas como coberturas vegetais cultivadas na entressafra para a formação de palhada exerce influência na sustentabilidade do sistema plantio direto (SPD). Com a decomposição, os nutrientes contidos na matéria seca (MS) são liberados e absorvidos pelas culturas em sucessão. O molibdênio (Mo) é um micronutriente que apresenta efeito tanto na enzima nitrogenase quanto na redutase do nitrato as quais são essenciais para a fixação biológica de nitrogênio (FBN). O presente trabalho teve por objetivo avaliar o efeito de doses de N em coberturas vegetais na soja com diferentes doses de Mo foliar, em sucessão, em região de Cerrado e sob SPD. O delineamento experimental utilizado foi em blocos casualizados no esquema fatorial 2 x 4 x 4 com três repetições. Os tratamentos utilizados foram: duas espécies de coberturas vegetais [sorgo – Sorghum bicolor L. Moench e milheto - Pennisetum glaucum (L.) R. Brown], quatro doses de N (0, 40, 80 e 120 kg ha-1) que foram aplicadas nas coberturas vegetais e quatro doses de Mo aplicadas via foliar na soja em sucessão (0; 12,5; 25 e 50 g ha-1). O cultivar utilizado foi o BRS Valiosa RR. Como fonte de N utilizou-se o nitrato de amônio (33% de N). Nas coberturas vegetais foi determinado a produtividade de MS, teor e acúmulo de N, P, K, Ca, Mg, S e Mo e a MS remanescente. Na cultura da soja realizaram-se as seguintes avaliações: teores foliares de N, P, K, Ca, Mg, S e Mo, estande, altura de inserção da primeira vagem, altura de planta, número de grãos por vagem, número de vagens por planta, número de grãos por planta, massa de 1000 grãos e produtividade. O milheto e o sorgo apresentaram acúmulo de MS semelhantes quando a semeadura ocorreu na primavera. Ambas as espécies utilizadas como coberturas vegetais apresentaram potencial para utilização em rotação/sucessão no SPD. A palhada de sorgo proporciona à cultura da soja maior estande e maior altura de plantas. A produtividade de grãos foi maior sobre a palhada de milheto. As doses de N aplicadas nas coberturas vegetais e as doses de Mo via foliar na soja não aumentam a produtividade desta oleaginosa cultivada em sucessão no SPD.
The choice of species to be used as cover plants cropped in no season to straw production exert influences in the sustainability of no tillage (SPD). With the decomposition, the nutrients contained in the dry matter (MS) are released and absorbed by crops in sucession. The molybdenum (Mo) is a micronutrient that had so effect in nitrogenase enzyme as in the nitrate reductase those are essential to nitrogen biological fixation (FBN). The present work had as objective to evaluate the N rates effect on cover plants in the soybean with differents Mo foliar rates, in sucession, in Cerrado region and under SPD. The experimental design used was in randomized blocks in factorial scheme 2 x 4 x 4 with three replications. The treatments used were: two species of cover plants [sorghum – Sorghum bicolor L. Moench e millet - Pennisetum glaucum (L.) R. Brown], four N rates (0, 40, 80 and 120 kg ha-1 ) that were applied in cover plants and four Mo rates applied on the leaves in soybean in sucession (0; 12,5; 25 and 50 g ha-1 ). The cultivar used was the BRS Valiosa RR. As N source was used ammonium nitrate (33% of N). In the cover plants were determinated the dry matter yield (MS), content and accumulation of N, P, K, Ca, Mg, S and Mo and MS remaining. At soybean were done the follow evaluations: leaf content of N, P, K, Ca, Mg, S and Mo, stand, first pod insertion, plants height, number of grains by pod, number of pods by plant, weight of 1000 grains and grains yield. The millet and sorghum showed similar MS accumulation when the sowing occurred in the spring. Both species used as cover plants showed potential to use in rotation/sucession in the SPD. The sorghum straw concerns to soybean crop bigger stand and plants height. The grains yield was bigger under millet straw. The N rates applied on the cover plants and the foliar Mo rates in the soybean didn‟t increase the grains yield of this oleaginous cropped in sucession in the SPD.

Orientador: Edson Lazarini
Resumo: A escolha de espécies a serem utilizadas como coberturas vegetais cultivadas na entressafra para a formação de palhada exerce influência na sustentabilidade do sistema plantio direto (SPD). Com a decomposição, os nutrientes contidos na matéria seca (MS) são liberados e absorvidos pelas culturas em sucessão. O molibdênio (Mo) é um micronutriente que apresenta efeito tanto na enzima nitrogenase quanto na redutase do nitrato as quais são essenciais para a fixação biológica de nitrogênio (FBN). O presente trabalho teve por objetivo avaliar o efeito de doses de N em coberturas vegetais na soja com diferentes doses de Mo foliar, em sucessão, em região de Cerrado e sob SPD. O delineamento experimental utilizado foi em blocos casualizados no esquema fatorial 2 x 4 x 4 com três repetições. Os tratamentos utilizados foram: duas espécies de coberturas vegetais [sorgo – Sorghum bicolor L. Moench e milheto - Pennisetum glaucum (L.) R. Brown], quatro doses de N (0, 40, 80 e 120 kg ha-1) que foram aplicadas nas coberturas vegetais e quatro doses de Mo aplicadas via foliar na soja em sucessão (0; 12,5; 25 e 50 g ha-1). O cultivar utilizado foi o BRS Valiosa RR. Como fonte de N utilizou-se o nitrato de amônio (33% de N). Nas coberturas vegetais foi determinado a produtividade de MS, teor e acúmulo de N, P, K, Ca, Mg, S e Mo e a MS remanescente. Na cultura da soja realizaram-se as seguintes avaliações: teores foliares de N, P, K, Ca, Mg, S e Mo, estande, altura de inserção da primeira vagem, a... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The choice of species to be used as cover plants cropped in no season to straw production exert influences in the sustainability of no tillage (SPD). With the decomposition, the nutrients contained in the dry matter (MS) are released and absorbed by crops in sucession. The molybdenum (Mo) is a micronutrient that had so effect in nitrogenase enzyme as in the nitrate reductase those are essential to nitrogen biological fixation (FBN). The present work had as objective to evaluate the N rates effect on cover plants in the soybean with differents Mo foliar rates, in sucession, in Cerrado region and under SPD. The experimental design used was in randomized blocks in factorial scheme 2 x 4 x 4 with three replications. The treatments used were: two species of cover plants [sorghum – Sorghum bicolor L. Moench e millet - Pennisetum glaucum (L.) R. Brown], four N rates (0, 40, 80 and 120 kg ha-1 ) that were applied in cover plants and four Mo rates applied on the leaves in soybean in sucession (0; 12,5; 25 and 50 g ha-1 ). The cultivar used was the BRS Valiosa RR. As N source was used ammonium nitrate (33% of N). In the cover plants were determinated the dry matter yield (MS), content and accumulation of N, P, K, Ca, Mg, S and Mo and MS remaining. At soybean were done the follow evaluations: leaf content of N, P, K, Ca, Mg, S and Mo, stand, first pod insertion, plants height, number of grains by pod, number of pods by plant, weight of 1000 grains and grains yield. The millet and sorghu... (Complete abstract click electronic access below)
Doutor

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Universidade Estadual Paulista (UNESP)
O presente trabalho teve por objetivo estudar as modificações de propriedades químicas e agregação de um Latossolo Vermelho de Cerrado, sob manejo com adubação orgânica e/ou mineral e com diferentes sistemas de cultivo. O experimento foi realizado na área experimental da Universidade Estadual Paulista - UNESP, localizada no município de Selvíria, MS, nos anos agrícolas 2003/04 e 2004/05. Os tratamentos constaram de três sistemas de cultivo do solo (convencional; cultivo mínimo e semeadura direta) e seis adubações (testemunha - sem adubação; adubação mineral-70 kg ha-1 de P2O5 e 80 kg ha-1 de K2O; adubação orgânica - esterco bovino-20 Mg ha-1; u adubação orgânica (esterco bovino)+ u da adubação mineral recomendada; 20 e 30 Mg ha-1 de lodo de esgoto). A agregação do solo foi modificada após 2 anos, sendo que os manejos com semeadura direta e cultivo mínimo apresentaram os melhores resultados, quanto aos adubos mineral e orgânicos, estes se destacaram em relação a testemunha. Para a massa de 100 grãos a utilização de adubos minerais e orgânicos proporcionou melhores resultados em comparação a testemunha, no entanto, para a produtividade foram semelhantes. Para produção de massa seca de sorgo o cultivo convencional foi melhor do que a semeadura direta e, o cultivo mínimo foi semelhante a ambos.
The present work had for objective to study the modifications of chemical properties and of the aggregation of a soil after two years of management with organic manuring and/or mineral under different preparation systems. The experiment was carried out in Selvíria, state of the Mato Grosso do Sul, Brazil, during the agricultural years of 2003/04 and 2004/05. The treatments were: Conventional-tillage, chisel tillage and no-tillage besides six manurings: control (no manuring), manuring mineral, organic manure, organic+mineral, 20 and 30 Mg ha-1 of sewage sludge. After two years of the application of the fertilizers, organic and/or mineral, an improvement was observed in the chemical properties of the soil in comparison with initial analysis. Regarding the aggregate stability of the soil, organic fertilizers and/or minerals and no-till and the minimum cultivation provided a better aggregation of the soil. To weight of 100 soybean grains there was significant difference try use of organic and mineral fertilization; however it was not observed for the production. To dry matter of sorghum the conventional preparation presented the largest values compared to the no-till and, the minimum preparation was similar the both.

Orientador: Edson Lazarini
Banca: Salatiér Buzetti
Banca: Carlos Alexandre C. Crusciol
Resumo: A cultura da soja vem sendo intensamente cultivada, no sistema plantio direto (SPD), na região do Cerrado. O solo, de baixa fertilidade e elevada acidez, e as altas temperaturas favorecendo a decomposição do material vegetal na superfície do solo, tem limitado o estabelecimento do SPD nesta região. Sendo assim, é de grande interesse a busca de alternativas que viabilizam a correção do solo e o incremento da palhada na implantação do SPD. Neste contexto, o objetivo deste trabalho foi avaliar culturas de cobertura, tipos e doses de calcário aplicadas na superfície do solo na implantação do SPD e seus efeitos na cultura da soja e nos atributos químicos do solo. O experimento foi conduzido na Fazenda experimental da UNESP - Campus de Ilha Solteira, localizada no município de Selvíria, MS em um LATOSSOLO VERMELHO Distrófico irrigado por pivô central. A área anteriormente foi cultivada com soja no sistema convencional. O sorgo e o milheto foram dispostos em faixa no sentido longitudinal da área experimental para facilitar a semeadura, enquanto que os tipos de calcário (PRNT de 100% e PRNT de 82%) e as doses (0,0, 0,25, 0,5, 1,0 e 2,0 vezes a calculada para elevar o V% a 60) foram distribuídos inteiramente ao acaso no sentido transversal da área. Foram avaliados os parâmetros de massa seca da parte aérea e porcentagem de cobertura do solo proporcionada pelas culturas de cobertura, estado nutricional das plantas de soja, características agronômicas da soja e atributos químicos do solo. O sorgo produziu maior quantidade de massa seca proporcionando maior cobertura do solo, porém a palhada de milheto foi mais duradoura na superfície do solo. A soja cultivada em sucessão ao sorgo, apresentou menor crescimento vegetativo e redução no número de vagens e massa de 1000 sementes. A aplicação superficial do calcário com PRNT de 100% proporcionou aumento ...(Resumo completo, clicar acesso eletrônico abaixo)
Abstract: In Brazil, the soybean is intensively cropped under non-till system on the Cerrado region. However the low fertility and pH values of the soil, and high air temperature conditions increase the organic matter decomposition on the soil surface, limiting the non-till system establishment. In this way, searches for alternatives that promote a good soil correction with plant coverage enhancement for a non-till systems establishment are needed. The aim of this work was to evaluate the cover crops, types and levels of limestone during a non-till system establishment and its effects on soybean cropping and soil chemical characteristics. The experiment was carried out at experimental farm of the UNESP, district of Selvíria, Mato Grosso do Sul State in a distrofic red latosoil irrigated with a center pivot. Sorghum and millet were disposed in a longitudinal strip direction from the experimental area to facilitate the sowing while the limestone types (PRNT 100% and PRNT 82%) and the levels of input (0.0, 0.25, 0.5, 1.0 and 2.0 times the prescribed level to elevate the V% to 60) were randomly distributed in a transversal way. The shoot dry mass production, the percentage of soil coverage by crops cover, the nutritional and characteristics of soybean plants and the chemical attributes of soil were evaluated. Sorghum showed high values of shoot dry mass than millet, however, the millet dry mass was more enduring on soil surface. Soybean cropped in succession to sorghum shown an decrease in vegetative growth, number of pods and fresh mass of 1000 seeds. On the other hand, the superficial liming with PRNT 100% provided an increase in the number of pods and consequently increases on yield of soybeans. Independently of granulometry the increase in levels of inputted limestone was directly proportional to decreasing on contents of Fe, Zn and Mn ions of soybean leaf tissues... (Complete abstract, click electronic access below)
Mestre

Thesis (M.Sc. (Pasture Science)) -- University of Limpopo, 2014
Forage sorghum is widely grown in South Africa as annual summer forage to supplement pasture production for sheep, beef and dairy cattle. A number of sorghum cultivars are available commercially, and periodically some cultivars are added while others are withdrawn from the market. The potential yield figures and the nutritive value of these forage sorghum cultivars are generally not known. The management practices that improve forage sorghum production and quality include the time of planting and time of harvesting. The genetic makeup of different forage sorghum cultivars also accounted for a portion of the production and quality. A field experiment was conducted at Dewageningsdrift Experimental Farm (DWD), Moloto, Gauteng and Nooitgedacht Agricultural Development Center (NGD), Ermelo, Mpumalanga to study the influence of planting date on the growth potential of different forage sorghum cultivars. Three planting dates were used: mid-December 2006, mid-January 2007 and mid-February 2007. Thirteen different cultivars were incorporated in the trial to evaluate influence of the breeding history. The cultivars were defoliated at three different stages: cut repeatedly at six weekly intervals (Dt 1), cut repeatedly when it reached a grazing stage (± 800 mm high) (Dt 2) and once at the silage stage (soft dough) (Dt 3). At DWD the average total dry matter (TDM) productions, for the six week cutting treatment (Dt 1), were 10760 kg/ha, 5195 kg/ha and 1944 kg/ha for December, January and February planting date respectively. For the same treatment, at NGT, the average TDM productions were 6396 kg/ha and 1737 kg/ha for December and January respectively. The February planting resulted in the poor germination and seedling emergency. The seedlings did not survive due to low temperatures. The minimum of 13 ºC and 11.8 ºC as well as the maximum of 24.1 ºC and 23.0 ºC in February and March were below the required germination temperature (15 ºC). The highest producers that is available in the market were Jumbo, Sentop, Piper, Kow Kandy, and Sugargraze. Defoliated repeatedly at grazing stage (Dt 2), at DWD, resulted in average TDM productions of 8541 kg/ha, 4950 kg/ha and 2683 kg/ha for December, January and February, respectively. At NGT the average TDM productions were 7769 kg/ha and 3010 kg/ha for December and January respectively. The highest producers were Jumbo, Kow Kandy, Piper, Sentop and Sugargraze. The average TDM productions at the silage stage (Dt 3), at DWD, were 17923 kg/ha, 15015 kg/ha and 2529 kg/ha for December, January and February respectively. At NGT the average TDM production iii was 11856 kg/ha and 5350 kg/ha for December and January, The highest producers were Jumbo, Sugargraze, Kow Kandy, Sentop and Kow Kandy.December planting proved to be the best planting date for optimum DM production, compared to later plantings in January and February. Keywords Forage sorghum, cultivars, planting dates, defoliation stages, grazing stage, silage

Sweet sorghum is a highly versatile C4 grass noted for its improved drought tolerance and water use efficiency relative to sugarcane. Sweet sorghum is well suited for ethanol production due to a rapid growth rate, high biomass production, and a wide range of adaptation. Unlike the 12-18 month growth cycle of sugarcane, sweet sorghum produces a harvestable crop in three to five months. Sweet sorghum and sugarcane crops are complementary and in combination can extend the sugar mill seasons in many regions of the world to an estimated 8 months. Seasonal growth and weather patterns both optimize and restrict production of each crop to specific times of the year, however these are different for the two crops. In addition to temporally spacing the date of harvest between crops, the genetic variability of maturity within the crops may also be used to extend the mill seasons; specific hybrids can be used and selected to maximize yield throughout the harvest season. Under favorable growing environments, sweet sorghum hybrids of all maturity groups produced sugar yields ranging from 2.8 to 4.9 MT/ha. Early/medium, late, and very late maturity hybrids planted during April, May, and June planting dates are necessary to maximize the mill season. In this study, early/medium maturity hybrids planted during April and May matured for harvest between late July and mid-August. June planting dates were unfavorable for early/medium maturity hybrids. In addition, late and very late maturity hybrids planted during April matured for harvest in late August; the additional growing season thus resulted in higher sugar yields. Timely planting of late and very late maturity hybrids in April, May, and June produce the maximum yields for harvests after mid August. Intermittent use of late and very late maturity hybrids can therefore extend sugar milling seasons into mid November if so desired.