摘要:

AbstractThree hybrids ofPennisetum americanumL. Leeke were analyzed for growth and photosynthetic components during early growth and compared with their respective parents. Growth in terms of shoot length, fresh weight and dry weight along with the chlorophylls, and Hill activity revealed better parental and/or mid parental heterosis in all the hybrids over their respective parents. However, PEPcase activity displayed heterosis only in BJ‐104. In other two hybrids no heterosis over the parents could be observed indicating thereby that the activity of this enzyme may not be rate limiting in parental lines.Nevertheless, it appears that in pearl millet hybrids improved photosynthetic apparatus as observed in chlorophyll contents and Hill reaction may be one of the early expressions of hybrid vigou

ISSN:0931-2250    

DOI:10.1111/j.1439-037X.1986.tb00040.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractDroughts are an ever‐present threat to tropical crops and pastures. One of the most difficult features of managing pastures in arid and semi‐arid regions has therefore been the variability in production from year to year. An understanding of the survival mechanisms of tropical pasture plants and the factors controlling grass/legume interrelations is a prerequisite to the establishment of secure bases for management recommendations. These aspects and management strategies were discussed.For increased agricultural productivity in order to avert famine, and efficient resource use in drought‐prone regions, pasture agronomists should pay attention to the characters most needing improvement in the suite of available tropical grasses and legumes that were disc

ISSN:0931-2250    

DOI:10.1111/j.1439-037X.1986.tb00041.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractSignificant increase in yield of rice and straw was obtained with zinc application during two years of experimentation. Among different sources tried, zinc sulphate proved better. An increase in the concentration and uptake of zinc and nitrogen was found with the application of zinc, whereas there was a reverse trend in the concentration and uptake of phosphorus and potassium.

ISSN:0931-2250    

DOI:10.1111/j.1439-037X.1986.tb00042.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractSensitivity of different agronomic crops to UV‐B radiation was studied under environmentally controlled conditions. UV‐B radiation reduced plant height, fresh weight, dry weight and ash contents. The reduction varied among the different species tested. Narrow‐leaved plants (mainly C4) were less sensitive to UV‐B than broad‐leaved plants (m

ISSN:0931-2250    

DOI:10.1111/j.1439-037X.1986.tb00043.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractIn a greenhouse trial, non‐mycorrhizal and mycorrhizal plants ofSorghum bicolorwere grown at three water regimes. The root length and root morphology ofSorghum bicolorwas monitored in two soils during 34 days. From 29 days on, total root length of mycorrhizal sorghum was greater than of non‐mycorrhizal sorghum in moderate and high water stress conditions. In soil A, at all water regimes a lower percentage of coarse roots and smaller root length per leaf area were found with mycorrhizal plants; in soil B, this was only the case in well watered conditions. In general, all root and water relation parameters were less affected by water stress when plants were mycorrhizal; this less sensitivity of mycorrhizal sorghum may increase the tolerance of the plant to drought. However, water relations of plants were indirectly enhanced by mycorrhiza via increased P upt

ISSN:0931-2250    

DOI:10.1111/j.1439-037X.1986.tb00044.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractA field experiment was conducted duringkhariff1984 in sandy clay loam soil under irrigated condition at the Tamil Nadu Agricultural University, Coimbatore, with a view (i) to find out the possibility of introducing short duration dwarf variety of sorghumCO 22as an intercrop with pigeonpea genotypes, (ii) to study the effect of different plant population levels and intercropping of sorghumCO 22on pigeonpea genotypes, and (iii) to find out compatible pigeonpea genotypes and plant population level for pigeonpea based intercropping system with sorghumCO 22.It was observed that increased plant density significantly increased the dry matter production, leaf area index (LAI) and crop growth rate (CGR) during early stages and reduced the net assimilation rate (NAR), relative growth rate (RGR) and CCR during later part of the growth. Intercropping of sorghumCO 22significantly reduced the dry matter production LAI, CGR, NAR and RGR. Plants in the intercropped stands recorded higher CGR, NAR and RGR during later part of the growth. Among pigeonpea genotypesCO 5was much affected due to intercropping with sorghumCO 22.

ISSN:0931-2250    

DOI:10.1111/j.1439-037X.1986.tb00045.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractDiallel‐cross designs have been used extensively in plant and animal breeding programs. In most cases, multiple traits are measured in the study, but the analyses are performed on each trait separately. The objective of this paper is to provide an alternative multivariate procedure so that the combining abilities among traits can be evaluated simultaneously and the interaction of combining ability and traits can be tested statistically.Numerical example is provided from data of a rice study. Three characters, panicles per plant, percent sterility, and 100 kernel weight were used in the analysis. Results showed that some parental lines with greater combining abilities in one trait may not be so good in another trait. Also certain crosses may be better for one trait but not necessarily as good for other trait

ISSN:0931-2250    

DOI:10.1111/j.1439-037X.1986.tb00046.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractFifty‐six accessions of multi‐cut Egyptian clover were compared at four experiments under different environmental conditions; i.e. location and season. Considerable variation existed for all the characters studied. The genetic variance exceeded the environmental variance for all the studied traits. Heritability was high for all characters studied. The expected genetic advance from selection of the superior 10.7% of the accessions as calculated from the combined data reached to 16.10, 17.50, 5.20, 20.60, 3.52 and 21.00 for mean plant height, seasonal fresh forage yield, mean dry matter percentage, seasonal dry forage yield, mean protein percentage, and seasonal protein yield, respectively. Both phenotypic and genotypic correlations among traits showed that mean plant height was positively correlated with each of seasonal fresh forage yield, seasonal dry forage yield, mean dry matter percentage and seasonal protein yield, but negatively correlated with mean protein percentage. Negative correlation were also found between mean protein percentage with seasonal fresh and dry forage yield.Over all experiments, pat‐coefficient analysis revealed that seasonal fresh forage yield had the highest positive direct effect on seasonal protein yield (0.841), followed by mean dry matter percentage (0.461). The mean protein percentage showed the minimum direct (0.172) and indirect influence on seasonal protein

ISSN:0931-2250    

DOI:10.1111/j.1439-037X.1986.tb00047.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractPlants of maize (Zea maysL.), spring barley (Hordeum vulgareL.) and broad bean (Vicia fabaL.) were raised in tubes filled with a soil‐sand mixture and supplied with nutrient solution. The nutrient supply was varied with regard to concentration and typ of compound of “N”. Due to the relatively high concentrations of “N”, dry matter of shoots and roots was reduced in comparison to the control; root morphology was affected in terms of root length and root thickness. The N‐compounds, used in the experiment, exerted quantitatively different influences on dry matter production and root morphology, NH4NO3being the N‐form which had the weakest detrimental effects. There was no specific response to NH+4or NO−3but a strong influence could be shown for NH4Cl and NaNO3. Probably not only the concentration of “N” and the form of “N” have a specific influence, but also the cations and anions associated with the N‐con

ISSN:0931-2250    

DOI:10.1111/j.1439-037X.1986.tb00048.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

Book Reviewed in this article:Spaar, D., H. Kleinhempel und R. Fritzsche (Herausgeber), Diagnose von Krankheiten und Beschädigungen an Kulturpflanzen. Diagnosemethoden (verantwortlich bear‐beitet von T. Wetze

ISSN:0931-2250    

DOI:10.1111/j.1439-037X.1986.tb00049.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY