Simulating Seed Number in Grain Sorghum from Increases in Plant Dry Weight

Gerik, T. J.; Rosenthal, W. D.; Vanderlip, R. L.; Wade, Leonard

doi:10.2134/agronj2004.1222

Cited by 22 publications

(21 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The expolinear relationship between grain yield and pre-anthesis PTQ indicates a threshold of 0.48 MJ m −2 d −1 per • C, which may be associated with a critical carbohydrate availability to develop spikelets found in sorghum [41]. Generally, grain yield increases linearly with PTQ [28,30], but in our study the relationship was analysed over a wider range of agro-climatic conditions allowing to identify a threshold value.…”

Section: Genetic Adaptation For Yield Responses To Environmentmentioning

confidence: 90%

Adaptation and performance of rice genotypes in tropical and subtropical environments

Jing

Spiertz

Hengsdijk

et al. 2010

NJAS: Wageningen Journal of Life Sciences

View full text Add to dashboard Cite

a b s t r a c tStandardized field experiments were carried out to study the performance of five rice genotypes derived from different germplasm in terms of yield, harvest index (HI) and grain quality at eight agro-ecological sites of the tropics and subtropics across Asia during 2001 and 2002. Considering that indica and javanica genotypes adapt to warm climatic conditions, and japonica genotypes to cool agro-climatic conditions, it is hypothesized that indica × japonica hybrids may combine high yields and good quality traits under a wide range of agro-climatic conditions. Grain yield, HI, protein content and amylose content varied considerably among genotypes and environments. Mean rice yields of genotypes ranged from 1.5 to 11 t ha −1 across the eight sites; on average yields were 7.2 t ha −1 under subtropical and 2.7 t ha −1 under tropical conditions. The much lower yields in tropical environments resulted from a low biomass as well as a low HI. Among the genotypes, the indica × japonica hybrid showed the highest yield under subtropical conditions, and a higher yield than the japonica genotypes and the indica × javanica hybrid but lower than the indica genotype under tropical conditions. Phenology of genotypes varied strongly across environments. Low yields at tropical locations were associated with a low light capture due to short growth duration. Post-anthesis light-use efficiencies and the photothermal quotient explained much of the variation in yield. Protein content varied among genotypes depending on location and year. Variation in amylose content of rice grains was mainly associated with genotypic differences and much less with environmental conditions, but contents decreased with higher post-anthesis ambient temperatures. The indica × japonica hybrid combined high yields with a favourable amylose content and showed a better ability to adapt to cool and to warm agro-climatic conditions than the indica or japonica genotypes. Our study showed the magnitude of yield penalties associated with growing rice genotypes in environments to which they are not adapted. The consequences of these findings for improved adaptation of rice are discussed.

show abstract

Section: Genetic Adaptation For Yield Responses To Environmentmentioning

confidence: 90%

Adaptation and performance of rice genotypes in tropical and subtropical environments

Jing

Spiertz

Hengsdijk

et al. 2010

NJAS: Wageningen Journal of Life Sciences

View full text Add to dashboard Cite

show abstract

“…However, the earlier differences observed in RGR were reflected in CGR and thereby affected biomass at harvest. Because plant biomass often increases exponentially with time in sorghum (Gerik et al, 2004), early seedling vigour has marked effects on crop growth, biomass and yield (Cisse and Ejeta, 2003;Ellis, 1992). In addition, the observed changes in CGR could also be explained by increased NAR and LAI.…”

Section: Effects Of N Treatments On Plant Growth and Biomass Productionsmentioning

confidence: 99%

Efficient rates of nitrogenous fertiliser for irrigated sweet sorghum cultivation during the post-rainy season in the semi-arid tropics

Kurai

Morey

Wani

et al. 2015

European Journal of Agronomy

View full text Add to dashboard Cite

Sorghum (Sorghum bicolor (L.) Moench) is a multipurpose crop with high tolerance to environmental stresses. To meet the increased demand for food and biofuel, current agricultural practices rely on the excessive use of inorganic nitrogen (N) fertiliser. However, excessive N fertiliser has resulted in negative environmental effects. In view of the varied N use efficiency (NUE) of plants under different environmental conditions, the aim of this study was to evaluate the efficient rates of N fertiliser in semi-arid tropics for sweet sorghum cultivation during post-rainy season by maximising NUE without compromising yield. Field experiments were conducted on two sweet sorghum cultivars with four different N fertilisation rates (0, 63, 90 and 150 kg N ha −1) during the post-rainy season in India. Grain and stalk yields increased with N fertiliser, but significantly only up to 90 kg N ha −1. The observed increases in grain yield were attributed by increases in kernel numbers. Corresponding with the differences in biomass, both relative growth rate (RGR) and crop growth rate (CGR) increased with N fertilisation rate up to 90 kg N ha −1. Component analyses of RGR and CGR revealed that both net assimilation rate (NAR) and leaf area index (LAI) significantly contributed with increasing rates of N fertiliser applications. Furthermore, studies of NUE indices showed that agronomic N use efficiency (ANUE, indicating yield production per unit of fertiliser N) responded comparably up to 90 kg N ha −1 , and decreased significantly thereafter. Analysis of ANUE components showed that the decline in ANUE at 150 kg N ha −1 was due to a decrease in physiological N use efficiency (PNUE), indicating that the absorbed N was not utilised efficiently for biomass and yield production, but merely accumulated. These results together suggest that 90 kg N ha −1 is an efficient N fertilisation rate suggested among the tested treatments for sustainable sweet sorghum cultivation during the post-rainy season in the semi-arid tropics.

show abstract

“…A similar method is used for sorghum in the model SORKAM: the number of seeds depends on the accumulation of plant dry weight between panicle branch and spikelet appearance or panicle elongation and anthesis. An empirical factor accounts for water stress (Gerik et al, 2004).…”

Section: Deterministic Modelling Of Fruit Abortionmentioning

confidence: 99%

Stochastic Dynamic Simulation of Fruit Abortion: A Case Study of Sweet Pepper

Wubs¹,

Heuvelink²,

Hemerik³

et al. 2011

Acta Hortic.

View full text Add to dashboard Cite

Abortion of reproductive organs diminishes yields in many crops. In indeterminate greenhouse crops, alternating periods of fruit abortion and fruit set exist, resulting in fluctuations in fruit yield. Factors affecting the level of abortion are e.g., the supply and demand for assimilates (source and sink strength, respectively), temperature and cultivar. However, simulation of fruit abortion is still a weak part of crop simulation models. Variation in fruit abortion exists between plants, which results in differences in the timing and the number of set fruits. Therefore, simulating fruit abortion with variation could give more realistic simulation results. The probability of a fruit to abort should be related to factors like source strength and sink strength. The more favourable the circumstances are for fruit abortion, e.g., low source strength or high sink strength, the more likely it is that the fruit aborts. Survival analysis estimates parameters quantifying the influence of explanatory variables on the abortion rate. Time-varying explanatory variables can be used in the analysis. In a case study, we used survival analysis to analyse a data set with observations on flowering, fruit abortion and fruit harvest for sweet pepper. Source and sink strength were used as explanatory variables. The resulting equation determining the probability of abortion per day was implemented in a simple simulation model to simulate fruit set. The model output, as an average of 100 plants, showed similar timing in the fluctuations in fruit set as the observations, although the amplitude of the fluctuations was in some cases underestimated. The percentage fruit set was simulated correctly.

show abstract

Simulating Seed Number in Grain Sorghum from Increases in Plant Dry Weight

Cited by 22 publications

References 16 publications

Adaptation and performance of rice genotypes in tropical and subtropical environments

Adaptation and performance of rice genotypes in tropical and subtropical environments

Efficient rates of nitrogenous fertiliser for irrigated sweet sorghum cultivation during the post-rainy season in the semi-arid tropics

Stochastic Dynamic Simulation of Fruit Abortion: A Case Study of Sweet Pepper

Contact Info

Product

Resources

About