The objective of this study, carried out over 2 years, was to evaluate the effect of soil properties on the response of maize (Zea mays L.) to zinc applications and relate these properties to soil test Zn for predicting the Zn status of soils considering the effect of environmental conditions. The relative yield, expressed as an index of crop response, was related through multiple regression to CEC (or clay), electrical conductivity (or exchangeable Na), and bulk density consistently throughout the two year period that included one relatively wet, cool and cloudy growing season when variations in relative yield were explained also by 0.5 M NaHCO3-extractable-P and organic C. A procedure is presented to establish limits for the soil properties and soil-test-extractable-Zn and to meaningfully combine them into a model to predict soil Zn status. A model that combined soil test Zn, texture and electrical conductivity was satisfactory for the purpose of prediction and for adoption for soil testing on a routine basis. The suggested approach may be suitable for designing models with soil properties associated with crop responses to micronutrients in other situations.

The influence of zinc application on yield, Zn concentration and its uptake by paddy crop (Oryza sativa) was studied in a pot experiment in alluvial soils from Gwalior district. All the soils having less than 3.0 ppm 0.1 N HCI-extractable soil Zn showed significant yield response to application of Zn. The latter also resulted in significant increase in Zn concentration and its uptake by the crop. The plant tissue Zn was found to be significantly correlated at 1 % level with the soil Zn (r=0.82) and Bray's per cent grain yield (r=0.82). Critical level Zn in rice plant taken from top 15cm of the plant was worked out by statistical procedure of Cate and Nelson and found to be 13.5 ppm below which response to applied Zn is expected. Wirkung der Zikdiingung und des Zinkgehaltes im Boden a d Reis (Oryzp sativa)Es wurde die Wirkung von Zinkdungergaben auf den Ertrag, den Zinkgehalt und die Zinkaufnahme von Reis in Alluvialbdden aus dem Distrikt Gwalior im GefaRversuch gepriift. Mehrertrage durch die Zn-Dungung waren zu beobachten, wenn die Boden weniger als 3.0 ppm 0,l n-HC1-extrahierbares Zn enthielten. AuBerdem nahmen Zn-Gehalt und Zn-Entzug der Pflanzen zu. Der Zn-Gehalt der PBanzen korrelierte signifikant mit dem Zn-Gehalt des Bodens (R = 0,82) und dem Relativertrag nach Bray ( r = 0,82). Der kritische Zn-Gehalt wurde in den oberen 15 cm der Reispflanzen mit Hilfe des statistischen Verfahrens von Cate und Nelson ermittelt. Danach ist bei Zinkgehalten der Pflanzen unter 13,5 pprn mit Mehrertragen durch die Zn-Dungung zu rechnen.

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Background: Alternaria cyamopsidis (Rang. and Rao) causes Alternaria blight of clusterbean and it is one of the significant disease of clusterbean. Studies were conducted to compare the Cultural, morphological and pathogenic variability among ten isolates of Alternaria cyamopsidis from clusterbean, in five districts of Rajasthan viz., Bikaner, Barmer, Churu, Hanumangarh and Jaipur. Methods: During 2016-17 exhaustive survey was conducted in clusterbean growing areas of Rajasthan and collected diseased samples of clusterbean caused by Alternaria. All the samples were processed for isolation, purification and their pathogenicity was proved in cagehouse and laboratory and standard methods were adopted for cultural and morphological variability study. Result: All the isolates showed variation in their morphological characters, i.e., colony color and shape; conidial number, size, width, length, shape and septation on PDA. Out of ten isolates two isolate, viz., AlcyJp1 and AlcyJp2 showed maximum colony diameter 89.50 and 86.30 mm, respectively. All the isolates varied in their spore length and width and virulent on the tested variety of clusterbean for virulence. AlcyJp1 was the most virulent and produced maximum (65.50%) disease intensity, followed by AlcyJp2 isolate (61.22%).

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