<div style="text-align: justify;">The response of hybrid rice to seasonal changes is largely unknown. This study presents the effort to assess the response of tropical hybrid rice to rainy and winter seasons in alluvial soils at Regional Research Sub-Station under Bidhan Chandra Krishi Viswavidyalaya, Chakdah, West Bengal. Five commercial tropical hybrid rice cultivars together with a local HYV were evaluated in randomized complete block design with three replications. The variety NPH-207 (Champion) produced taller plants and recorded significantly higher number of effective tillers than the local HVY (Satabdi) did during both the seasons. The cultivar NPH-8889 (Karishma) recorded the maximum chlorophyll content at all dates of observations and it was statistically at par with NPH-207 (Champion). The values of all measured yield components were higher in the hybrid cultivar NPH-207 (Champion) in comparison with any other tested cultivars. Consequently, NPH-207 (Champion) produced significantly higher grain and straw yield, accounting 67.9 and 50.1% more than those obtained from HYV in rainy season, while 98.2 and 103% more than those obtained from HYV in winter season, respectively. The significant and positive correlations with grain yield were observed between plant height, 1000 grain weight and chlorophyll content at 30 DAT both in rainy and winter season.</div>

Differential growth and yield response of hybrid rice (<em>Oryza sativa</em> L.) to seasonal variability

<div><strong>Background:</strong> It is expedient to reduce or remove a negative effect of replant disease on new plantations after the old uprooted ones. To solve this problem, it is necessary to carry out the direct researches aimed at identifying the reasons for a negative effect of toxic soil conditions on young fruit plantations.<br />
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<strong>Methods: </strong>A vegetative trial, aimed at studying the effect of replant disease on the planted young apple trees after the uprooting of a 34-year-old apple plantation which was grown on the plots after a 50-year-old experimental orchard with apple fertilization systems, was established in spring of 2019.&nbsp;<br />
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<strong>Result: </strong>It has been found out in a vegetative trial that the growth of young apple trees weakens considerably in the first two years after planting one-year-old trees. The neutralization of replant disease, when dark grey opodzolic heavy loam soil was fertilized with manure, took place due to enriching it with organic substances. As a result, all the indicators of soil fertility increased and different bio-toxic compounds, which had a negative effect on mineral nutrition of young fruit plants, on their growth process and fruiting, neutralized faster and more intensively.</div>


Differential growth and yield response of hybrid rice (Oryza sativa L.) to seasonal variability

Feasibility to Neutralize Replant Disease under the Recultivation of an Apple Orchard