The wide diversity of seasonal flowering and fruiting with linkages to leaf flush time and leafless period reflect the fact that variable reproductive and survival strategies evolved in tree species under a monsoonic bioclimate. Flowering periodicity has evolved as an adaptation to an annual leafless period and the time required for the fruit to develop. The direct relationship between leafless period (inverse of growing period) and time lag between onset of vegetative and reproductive phases reflects the partitioning of resource use for supporting these phases. Predominance of summer flowering coupled with summer leaf flushing seems to be a unique adaptation in trees to survive under a strongly seasonal tropical climate.

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Keywords:tropical dry forests / deciduousness / wood density / leaf mass per area / leaf strategy index Abstract • In seasonally dry tropical forests deciduousness (leaflessness) is an important strategy of trees to survive in water stress period during summer. Deciduousness is a reflection of interacted effect of seasonal drought, tree characteristics and soil moisture conditions.• The present study aims to document the diversity in leaf pheno-phases in terms of duration of deciduousness (which is reciprocal to growing season length), wood density, leaf mass per area (LMA) and leaf strategy index in 24 important tree species growing in the Vindhyan dry tropical forest in India.• On the basis of phenological observations, the tree species were categorized into two main groups: leaf exchanging species exhibiting overlapping periods of leaf fall and leaf flush, and deciduous species whose timings of leaf flush and leaf fall differ resulting in a time lag (deciduousness) between the completion of leaf fall and initiation of leaf flush. Presence of wide range of deciduousness duration (from ca. a week to 7 months) among dry tropical trees indicates large variations in their growing season length. In the tree species studied, as the duration of deciduousness increased, leaf flushing period decreased significantly but leaf fall period showed little variation.• Differing deciduousness in tree species exhibited substantial differences in their leafing (vegetative growth) pattern, as reflected by ratio of durations of leaf flush to leaf fall (leaf strategy index). Across different species, duration of deciduousness was significantly positively correlated with leaf strategy index, and significantly negatively correlated with both wood density and LMA.• Wide variations in deciduousness, leaf strategy index, wood density and LMA in the 24 species investigated indicate considerable functional diversity in tree species growing in Vindhyan dry tropical region. Variation in seasonal duration of deciduousness among species is reflections of differences in tree functional traits like stem wood density, leaf strategy index and LMA. Mots-clés :forêts tropicales sèches / défoliation / densité du bois / masse de feuilles par unité de surface / index de stratégie de la feuille Résumé -La diversité des défoliations et les traits phénologiques d'arbres clés de la forêt sèche tropicale indienne.• Dans les forêts sèches tropicales saisonnières, la défoliation est une stratégie importante des arbres pour survivre dans les périodes de stress hydrique durant l'été. La défoliation est un reflet de l'interaction entre la sécheresse saisonnière, les caractéristiques des arbres et les conditions d'humidité du sol.• La présente étude vise à documenter la diversité des phénophases des feuilles en termes, de durée de la défoliation (qui est réciproque à la durée de la saison de croissance), de densité du bois, de masse foliaire par unité de surface (LMA) et d'indice de stratégie des feuilles chez 24 importantes espèces d'arbres poussant dans la for...

Tillage and crop residue management play an imperative role in soil physico-chemical properties that eventually affects crop productivity. The objective of the study to find out a compatible combination of tillage and crop residue management for achieving sustainable food production by improving soil properties, providing favorable environment to crop plants. Secondly, managing crop residues effectively to reduce environmental pollution arising due to crop residue burning. With this aim, a field experiment was conducted on six years continued running experiment under conservation agricultural practices during rabi season of 2019–20 on chickpea. The experiment was comprised of five tillage operations with or without crop residue in main plot and three levels of nutrients in sub plots laid out in split plot design with three replications. Reduced Tillage with 60cm residue height (RT60) was recorded higher growth and yield attributes over conventional tillage practice that attributed to economic yield enhancement. The percent yield increment under NT and RT with 30 and 60cm height residue retention varied from 6.91% to 9.67% over conventional tillage. Maximum grain (2380 kg ha-1) and biological output (5762 kg ha-1) was recorded under RT60 (T4), which ascribed to higher net return (Rs 60551 ha-1) and benefit-cost ratio (2.97). The augmentation in net monetary benefit among tillage systems was lies between 24.32% to 37.78% over conventional tillage. The seed protein content ranged between 20.38 to 21.69% among the treatments. Moreover, total N uptake was maximum under RT60, while total P and K uptake was higher in No Tillage with 30cm residue height (T1). No-Tillage with 60cm residue height (NT60) recorded relatively higher soil moisture content (SMC) (22.71 and 15.40%). Treatment NT30 accrued relatively higher value of soil bulk density (1.42 Mg m-3) followed by NT60 and RT60 in comparison to conventional tillage (1.34 Mg m-3). In conclusion, NT and RT with 60cm residue height along with STCR (N3) nutrient dose was found effective for sustainable food production.

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