Development Of Cotton Plants Research Articles

Effect of Exclusion of Ambient Solar Uv-A/B Components on Growth and Antioxidant Response of Cotton (Gossypium Hirsutum L.)

The influence of ambient solar UV-A or UV-B radiation on growth responses was investigated in three varieties of cotton (Gossypium hirsutum L.) after exclusion of solar UV-A/B radiation: JK-35, IH-63 and Khandwa-2. Cotton plants were grown from seeds in UV-exclusion chambers lined with selective UV filters to exclude either UV-B (280–315 nm) or UV-A/B (280–400 nm) from the solar spectrum under field conditions. Excluding UV-B and UV-A/B significantly increased plant height, leaf area and dry weight accumulation in all three varieties of cotton. The varieties differed considerably in their sensitivity to ambient UV-A/B. Khandwa-2 was most sensitive and JK-35 least sensitive to ambient solar UV. We monitored the activity of the antioxidant enzymes superoxide dismutase (SOD), ascorbic acid peroxidase (APX), glutathione reductase (GR) and guaiacol peroxidase (GPX), as well as the level of the antioxidant ascorbic acid (ASA), in primary leaves of the most UV-sensitive variety (Khandwa-2). The level of UV-B-absorbing substances was significantly decreased by exclusion of solar UV-B and UV-A/B. Exclusion of solar UV decreased the activity of all the antioxidant enzymes monitored and the level of ascorbic acid versus control plants (+UV-A/B) grown under filters transparent to solar UV. Reduction of the antioxidant defense after UV exclusion indicates that ambient solar UV exerts significant stress and induces some reactive oxygen species to accumulate, which in turn retards the growth and development of cotton plants. Ambient solar UV stresses cotton plants, shifting their metabolism towards defense against solar UV. Exclusion of solar UV eliminates the need for that defense and leads to enhancement of primary metabolism.

Desenvolvimento inicial do algodoeiro em resposta ao armazenamento de sementes tratadas com Cloreto de Mepiquat

O trabalho objetivou avaliar a manutenção do efeito do Cloreto de Mepiquat no desenvolvimento inicial das plantas de algodoeiro em função de doses e formas de aplicação do regulador e armazenamento das sementes tratadas. Sementes do cultivar IPR 120 foram tratadas com soluções de Cloreto de Mepiquat (250 g i.a. L-1) nas doses 0,0; 5,0; 10,0; 15,0 e 20,0 g i.a. kg-1 de sementes, via embebição por 12 horas e, via aplicação direta nas sementes. Ao zero; 60; 120 e 180 dias após a aplicação dos tratamentos as sementes foram semeadas em vasos e, semanalmente foram determinadas a altura e a área foliar e, aos 28 dias, o diâmetro do caule e matéria seca de caules e folhas. Os dados foram submetidos à análise de variância e a comparação de médias pelo teste de Tukey a 5%, sob o delineamento inteiramente casualizado, com quatro repetições, em esquema fatorial de 5 x 2 (doses x formas de aplicação), independentemente dos períodos de armazenamento. As médias de doses foram submetidas a estudos de regressão. Independente da forma de aplicação, o Cloreto de Mepiquat reduz diâmetro do caule, matéria seca de caule e folhas, área foliar e altura de plantas. A forma de aplicação e o armazenamento das sementes tratadas por até 180 dias não interferem na ação do regulador. A ação reguladora de crescimento do Cloreto de Mepiquat perdura, pelo menos, até os 28 DAE das plantas, independente da forma de aplicação, dose utilizada e período de armazenamento das sementes tratadas.

Effect of silicon and acibenzolar-s-methyl on colored cotton plants infested or not with Aphis gossypii Glover (Hemiptera, Aphididae)

Effect of silicon and acibenzolar-s-methyl on colored cotton plants infested or not with Aphis gossypii Glover (Hemiptera, Aphididae). The aphid Aphis gossypii is an insect pest that causes damage mainly at the beginning of the cotton plant development. The effect of resistance inductors silicon and acibenzolar-s-methyl (ASM) on the development of colored cotton plants were researched in the presence and absence of A. gossypii. Three colored cotton cultivars were sown in pots and individually infested with 25 apterous aphids, 13 days after the application of the inductors. Fifteen days after plant emergence, the silicon was applied at a dosage equivalent to 3 t/ha and acibenzolar-s-methyl in 0.2% solution of the product BION 500®. After 21 days of infestation the following parameters were evaluated: plant height, stem diameter, dry matter of aerial part and root, and total number of aphids replaced. It was verified that the plant height was reduced in the presence of aphids and all variables were negatively affected by the application of ASM. However, silicon did not affect plant development.

Effect of rain drop washes on soil fertility in cotton production zone of Burkina Faso

Crop production in the Sahel is limited by nutrients availability. The study aimed to estimate the contribution of avifauna, crop rotation and trees to soil fertility and crop production improvement. Pot experiment was carried out with soils sampled in Faidherbia albida parklands in cotton production zone of West Burkina Faso. The treatments consisted of two levels of sampling sites (outside and under the crown of Faidherbia albida), three types of previous crop (fallow, maize and sorghum) and two levels of fertilization (normal rain drop and raindrop washes). Results showed that cotton plants height were affected by sampling site and previous crop between 30 and 80 days after sowing. Rain drop washes contained nutrients that can help to improve soil fertility although their nutrients level in the soil is too small to have an impact significant on cotton plant development. No significant difference was observed between factors for the number of nodes and generative branches except for sampling site. Nutrients content in cotton plants was affected by the soil sampling site, the previous crop and the fertilization.

Cold temperature exposure at 10°C for 10 and 20 nights does not reduce tissue viability in vegetative and early flowering cotton plants

In Australia, temperatures below 11°C (called cold shocks) were believed to retard cotton (Gossypium hirsutum L.) growth, development and yield. Recent studies, however, have suggested that temperatures lower than this did not impede cotton development beyond normal developmental responses to cool temperatures. This paper aims to test the hypothesis that cold exposure to 10°C for 10 and 20 nights does not reduce tissue viability in vegetative and early flowering cotton plants. Cold temperatures at 10°C for 10 and 20 consecutive nights were imposed on cotton plants, grown in both controlled temperature glasshouses and outdoors, at the vegetative seedling and early flowering stages. Extreme temperature tests at 2, 5 and 7°C for two nights were also imposed to generate tissue damage for comparison. 2,3,5-Triphenyl tetrazolium chloride (TTC) tissue viability (testing for mitochondrial activity), relative electrical conductivity (REC, testing for membrane integrity), leaf chlorophyll fluorescence, leaf photosynthesis, plant dry weight and yield were measured. Only exposure at 2°C for two nights showed negative effects in the TTC and REC tests, and leaves of these plants died soon after exposure. There were no consistent negative effects in the TTC and REC tests for all treatments at 10°C for 10 and 20 nights compared with the respective controls, suggesting that there was no structural or functional damage to leaves. In support of these findings, leaf photosynthesis and both light- and dark-adapted chlorophyll fluorescence for the 20 nights at 10°C treatment were occasionally below the controls but recovered quickly, suggesting that only temporary dynamic photoinhibition occurred. Cotton plant development was delayed following 10 and 20 nights at 10°C owing to reduced degree day accumulation. These data support previous work that cold temperatures at 10°C for up to 20 nights would be unlikely to result in yield reduction as a consequence of plant damage, and also that crop development can be estimated with degree days without an adjustment for cold shock. The use of TTC and REC has potential for novel detection of tissue damage for cotton at extreme temperatures.

Impact of short-term exposure to cold night temperatures on early development of cotton (Gossypium hirsutum L.)

Regression analysis of field data has indicated that minimum daily temperatures below 11°C delay the development of cotton (Gossypium hirsutum L.) seedlings beyond what would be expected based on the accumulated degree-day sum. In Australian cotton production systems, events where the minimum daily temperature falls below this value are referred to as ‘cold shocks’. The number of cold shocks is used by growers and advisors in assessing retardation of crops in their areas. However, this effect has not been tested explicitly. The aim of this work was to empirically assess effects of cold shock on pre-flower development of cotton plants. Cotton seedlings were grown in controlled-temperature glasshouses. Plants were transferred to cold chambers ranging from 5 to 22°C during the night period for durations from 3 to 10 days. Negative effects were not seen until plants had been exposed to at least 10 nights at 10°C, or for at least 5 nights at 5°C. When differences were generated it did not delay development to first square any more than 4 days, nor was the effect consistent. These differences translated into delays to first flower, but had little effect on plant morphology, or on dry weight measured soon after flowering. In one experiment, a significant reduction in leaf photosynthesis was measured at two times of day on the day after cold shock at 5°C. Improving understanding of the effects of temperature extremes on cotton growth and development will help in developing more functional decision-support tools and field management strategies.

Monitoring the Growth and Development of Cotton Plants Using Main Stem Node Counts

Monitoring the Growth and Development of Cotton Plants Using Main Stem Node Counts

Influence of Meloidogyne incognita and Thielaviopsis basicola Populations on Early-Season Disease Development and Cotton Growth.

Microplot studies were used to examine the effect of various population densities of Meloidogyne incognita and Thielaviopsis basicola on cotton-plant development and disease severity. Plots were infested with 0, 20, or 100 T. basicola chlamydospores/g and 0, 5, or 10 M. incognita eggs and juveniles/cm3 of soil in a factorial arrangement in 1997 and 1998. Combinations of M. incognita and T. basicola reduced plant survival in both years compared to the noninfested control, except in 1998 for the high rate of T. basicola over all nematode rates. Plant height-to-node ratios were reduced by pathogen combinations compared to the noninfested control or to either pathogen alone. Plant dry weight was reduced by M. incognita in 1998 and the high rate of T. basicola in 1997. Root necrosis was increased by increasing rates of T. basicola in 1997 and by M. incognita over all rates of T. basicola in both years. Colonization of root tissue by T. basicola was increased by the low inoculum density of the nematode at 20 CFU/g soil in 1997 and 100 CFU/g in 1998. Nematode reproduction with the high M. incognita treatment rate was reduced in both years of the study by the high T. basicola rate. This study suggests the importance of population level of each pathogen to the severity of disease and confirms the potential of this disease interaction to impact cotton production.

Generation of mechanistic variability in a process-based object-oriented plant model

A cotton crop model based on individual plant developmental behavior and variability was developed. Object-oriented simulation (OOS) provided the conceptual basis for the new model structure. The procedural model, COTSIM, provided the theoretical background for cotton plant development. Data collected during 1987 from field-grown cotton were used for model development and verification, and data from 1988 were used for model validation. The model predicted mass accretion and production of organs within the patterns and magnitudes observed in the field. The model also predicted crop development aspects that had not previously been described by procedural models. Age and size of leaves and fruit and associated developmental variability were included in the model through representation of objects and their variable behavior defined by their position on the plant and how this constrains their growth. Observed variability was the result of the aggregate behavior of components. Variability in our OOS model is an output as opposed to being an input in most procedural plant models. The model has recreated both realistic plants and populations in a mechanistic simulation. Object-oriented models are an important step towards common structures and languages for model design and the development of simulations. It was noted that increased mechanistic detail resulted in an increase of procedure calls (messages) and a five-fold increase in model run time.

Concept for Monitoring the Growth and Development of Cotton Plants Using Main-Stem Node Counts

Management efficiency in cotton (Gossypium hirsutum L.) can be improved by implementing strategles that may be adjusted in response to expected or realized changes in plant growth and development. We propose that successive counts of main-stem nodes bearing sympodia with a preflower fruiting structure in the first position are practical, dynamic measurements of plant development. A technique of monitoring number of main-stem nodes above the sympodial branch bearing a white flower in the first position from the main axis (NAWF) was investigated. The physiological basis of NAWF was established by relating NAWF to other measurements of crop growth and yield. A critical value of NAWF was determined by retention, size, and number of seed associated with first-position bolls. In separate tests, influences of cultivars, plant densities, irrigation, and two insect pests on NAWF were evaluated. The number of NAWF was closely related to variation in canopy photosynthesis indicating that growth activity of the crop can be monitored by NAWF. Based on individual boll measurements, potential economic value of flowers declined rapidly as NAWF approached 5.0. From regression equations of NAWF by days from planting, the number of days to NAWF of 5.0 (representing the last effective flower population) were calculated and used to distinguish effects of the management factors on plant development. Increased precision and confidence in end-of-season management decisions will likely be the first major benefit of this monitoring technique. As effects of additional management factors on NAWF are established, manipulation of the effective fruiting period and developmental pace of the crop should be possible by various combinations of factors, thereby providing a useful management tool.

Trifluralin effects on the development of cotton in arid zone soils

Summary: The effect of trifluralin on the growth and development of cotton plants in low-organic-matter soils from the northern Negev of Israel was studied. Trifluralin exhibited linear sorp tion isotherms on these soils, Trifluralin and dinitramine losses from soils under varying moisture regimes and application practices were determined in open systems. The data were fitted to both first-order and biexponential kinetic equations. In about 50% of cases the biexponential kinetic model provided a better fit to the data, but no relationship could be found between the model parameters and environmental or soil properties. Losses were generally greater at field capacity than at 50% field capacity, and at 27°C than at 15°C, and in soils with a lower organic matter content. The trifluralin application rate was negatively correlated with vegetative growth parameters of cotton, but the correlation became weaker with increasing soil organic carbon content. Trifluralin delayed boll production in coarse textured soils, the longest delay occurring at higher application rates. It is concluded that in light soils that contain very little organic matter, trifluralin rates must be maintained at the minimum level required for adequate weed control to prevent damage to crops.

Pink Bollworm: 1 Seasonal Oviposition, Egg Predation, and Square and Boll Infestations in Relation to Cotton Plant Development 2

Native pink bollworm, Pectinophora gossypiella (Saunders), female moths oviposited principally on vegetative cotton plant parts until mid-July, on vegetative cotton plant parts and bolls until mid-August, and principally on cotton bolls thereafter. Eggs on bolls were placed on the inside surface of bracts or under the calyx. Squares were not attractive oviposition sites. More eggs were laid on bolls ca. 3.2 cm in diameter than were laid on bolls ca. 1.8 cm in diameter. Predation of eggs placed on cotton terminals was highest early in the season and decreased thereafter.

The effect of growing alfalfa on subseouent cotton plant development and on nitrate formation in peat soil

When cotton was grown in Hula peat soil following alfalfa, the germination, growth and yield were lower than when it followed wheat or bare soil. Results indicated that the formation of N-NO3 in the soil was reduced by alfalfa crop growth, or when alfalfa root leachate was applied to bare soil. The inhibition of nitrification appeared to be due to substances originating in the plant and released by the roots. It is suggested that saponine, which is known to be released by alfalfa roots, may be responsible for this effect.

Effect of Time and Rate of Application of Two Growth Retardants on Growth, Flowering, and Yield of Upland Cotton1

Six experiments were conducted at four locations in Israel in order to evaluate the effect of two growth retarding chemicals, CCC and CMH, on plants of Upland cotton, Gossypium hirsutum L. When sprayed during the first week of flowering, CCC at 50 and CMH at 480 g a.i./ha retarded the increase in height of cotton plants without adversely affecting lint yield or quality. These treatments caused a small reduction in flower production, but this was not associated with a decrease in yield. In some of the experiments, the increase in plant height following treatment was reduced by as much as 50%. Application of CCC at the rate of 100 g a.i./h at the beginning of flowering significantly reduced lint yield in one experiment. Increasing the rate of CMH to 720 g a.i./ha produced no harmful effects.When CCC or CMH were applied in the middle of the flowering period, they were less effective in reducing plant height. These results indicate that both CCC and CMH may be used to arrest excessive vegetative development of cotton plants, and that the optimum time of application is the beginning of flowering.

Some Aspects of Respiration and Respiration Inhibitors in Low Temperature Effects of the Cotton Plant

Respiration of leaf tissue from cotlon plants in the nine leaf stage was found to be severely reduced at temperatures below 15°C. In another study, young cotton plants were exposed to chilling temperature (2.8°C) for 72 hours and the ability of the plant tissues to recover respiration at normal temperatures (15 and 25°C) was examined at periodic intervals. Chilling exposures of 12 hours injured cotton tissues as indicated by increased respiratiou of leaves and roots at 25°C. Further chilling malerially reduced the capacity of the leaves to re-estahlish normal respiration rales at higher temperatures. Picolinic acid, Dexon and matonate were used to study the influence of respiratory inhibitors on the chill damage of the collon plants. The chemicals were applied six hours before cold exposure aud fhe growth and development of cold injured plants was studied to indicate the effectiveness of the treatments. Tissue weights at the final harvests indicated that picolinic acid and Dexon treated plants recovered better after cold injury than the untreated plauts. The results suggest thai 15°C may be a critical temperaliire for many physiological processes of the cotton plant because the supply of energy needed for plant reactionsis restricted due to inadequate respiration. They also indicate that the disturhances in respiration are among the early effects of chilling colton plants and may be the cause of delayed growth and development of cotton plants subjccled to non-lethal chilling exposures. It is concluded that chemicals like picolinie acid and Dexon may he effective through protection of specific systems rather than a general reduction of respiration.

Ensaios sôbre capação e desbrota do algodoeiro

São estudados 44 resultados anuais de ensaios, realizados durante o período de 1930 a 1942, em diversas localidades do Estado de São Paulo. O objetivo, foi averiguar a influência sôbre a produção e certas características econômicas do produto, que exerce a extirpação do brôto apical do algodoeiro - capação - e também a dos brotos terminais dos ramos monopodiais - desbrota, Essas operações, executadas em diferentes fases do desenvolvimento das plantas - no início, no auge e no declínio do florescimento - foram comparadas com testemunhas (sem extirpação). Os estudos não revelaram melhoria na produção de algodão em caroço por hectare, atribuíveis a essas operações. Ao contrário, quando se procedeu a capação no início do florescimento ou a desbrota em qualquer daquelas fases, a produção tendeu a diminuir. Nenhuma influência foi constatada sôbre o precocidade, porcentagem de fibra, comprimento de fibra, índice de fibra, pêso de 100 sementes e pêso de um capulho (semente + fibra). Essas conclusões concordam com aquelas a que têm chegado os que estudaram o mesmo assunto em outras regiões algodoeiras do mundo. Tais operações monstraram-se desaconselháveis. Elas implicariam em maiores dispêndios de tempo e de dinheiro, sem elevar a produção, podendo mesmo deprimi-la. Indiretamente, agravariam os prejuízos, por demandarem tempo e recursos em detrimento de práticas comprovodamente úteis, provocando, ainda, em virtude dos espaçamentos cerrados que se empregam atualmente, maior entrelaçamento dos galhos nas ruas do algodoal, dificultando os tratos culturais e o combate às pragas.

Studies on the Cultivation of Upland Cotton, Especially in Regard to Its Blooming and Ripening : III. The effects of different sowing dates on the numbers of convolution in cotton fibre

The experiments on the effects of blooming and ripening states of Upland cotton (Kanno No.1) on the numbers of convolution in cotton fibre of bolls arranged at vertical position were conducted by varying the sowing dates from May 7 to July 5 at 15 days intervals. The results obtained were as follows; 1) The numbers of convolution tend to decrease as the sowing dates are later and the ripening days become longer, but at later sowing after June they become constant regardless of vertical positions or of ripening days. 2) In the cotton fibres with ripening days more than 74∼78 days, the numbers slowly decrease in May 7 sowing but take a constant value (20) in May 22 sowing. 3) In the fibre required 74∼78 days for ripening, the average accumulated temperatures per day for cell-wall thickning were calculated as about 19.5 °C, and this is minimum temperature required to the secondary thickning of cellulose of cotton fibre. 4) The changes of the numbers of convolution do not coincide with our presumption even under optimum conditions except May 7 sowing with normal chang. So, we assume that the cell-wall thickning of cotton fibres is more directly affected by vegetative growth of plant itself than temperature. Then, the early sowing is preferable for the increase of the numbers of convolution because of it will bring about the complete vegetative development of cotton plant

INfluence of Ultra-Short Electromagnetic Waves on the Development of Cotton Plants

INfluence of Ultra-Short Electromagnetic Waves on the Development of Cotton Plants

Further studies on the Carbon dioxide factor in the Air and soil layers near the ground

This paper is in continuation of an earlier one by the author which appeared in this journal. It deals with the study of carbon dioxide content of the soil air of a sugarcane field. It is shown that the carbon dioxide content of the soil air is subject to local variations. An attempt has been made to see whether this local variation of soil air carbon dioxide is in any associated with the vigyour of the sugarcane plants. It is found, as a result that greater concentration of soil an carbon dioxide is Associated with taller plants and larger foliage development.
 The paper also describes A pot-culture experiment performed to compare the development of cotton plants irrigated with carbonated water. Plants grown under irrigation with carbonated water are found to be taller and having greater foliage development.

EFFECTS OF ALPHA–NAPHTHALENEACETIC ACID AND ALPHA–NAPHTHALENEACETAMIDE ON THE DEVELOPMENT OF THE COTTON PLANT

DESPITE THE extensive literature on effects of growth substances on development of plants, there are very few reports on influences of growth substances on cotton plant. While there have been a number of attempts to reduce boll abscission by use of growth substances, these have not been successful and few of them have been reported in literature. Dunlap (1945) reported negative results when he used several growth substances including naphthaleneacetic acid, and Eaton and Rigler (1945) stated that the present information does not permit any well-defined application of observation or theory to relations between hormone activity and shedding of cotton bolls, but some of marked differences between cottons in extent to which shedding occurs would seem to preclude possibility that in all cases this shedding can be attributed solely to nutritional relations. Except for limited amount of work on growth substances in relation to boll shedding, there has apparently been no work done on influences of growth substances on cotton. Any adequate review of influence of growth substances on plant development in general would be unwieldy and unnecessary here, so further citations of literature will be restricted to papers pertinent to discussion which appears later in this paper. The present study was initiated primarily to investigate possible influence of growth substances on boll abscission, but other effects were also observed and measured. As experiment progressed it became apparent that a general study of effects of growth substances would be more valuable than a specific studv of abscission, especially since so little has been reported on effects of growth substances on development of cotton plant. The results show that a-naphthaleneacetic acid, and to a lesser degree a-naphthaleneacetamide, have definite effects on growth and development of cotton plant. In general, growth was inhibited rather than stimulated by treatments, and it is unlikely that any of effects are of interest from standpoint of agronomic application, either as regards boll abscission or otherwise. 1 Received for publication April 23, 1949. This paper is a complete revision and condensation by junior author of a thesis submitted by senior author (1948) in partial fulfillment of requirements for degree of master of science at A. and M. College of Texas. The authors wish to acknowledge with thanks suggestions made by Dr. A. A. Dunlap, checking of statistical analyses by Prof. C. B. Godbey, critical reading of this manuscript by Dr. Frank M. Eaton, and testing of cotton fibers by Mr. J. L. Watson. METHODS.-Several seeds of Stoneville 2B variety of cotton (Gossypium hirsutum L.) were planted in each of a number of 2-gal. glazed jars on February 28, 1948, and by March 6 plants had been thinned to one per jar. The plants were maintained in fertile soil under good greenhouse cultural conditions throughout experiment, and