Crop growth is negatively influenced under water-stress conditions, which is among the most yield-limiting factors significantly decreasing crop yield. This study evaluated the effect of water-deficit stress on physiological, bio-chemical and yield attributes of wheat (Triticum aestivum L.) under both constantly wet and water-stressed conditions on two wheat varieties (UJALA-14, SARC-4). Further, the combined impacts of crop genetic variability and organic manuring in soil was studied for overcoming the partial drought stress in wheat. Treatments of different levels of irrigation water alone or with farmyard manure (FYM) @ 20 Mg ha‒1 were compared as: constantly wet irrigation (control), irrigation intensity equal to field capacity (FC), ½ FC + FYM, and ¼ FC + FYM. Crop growth, physiological and chlorophyll as well as sodium and potassium contents were measured. The findings of current study exhibited that shortage of water had negative effects on growth, physiological, bio-chemical and yield attributes of wheat. Genotype SARC-4 exhibited superior growth response having constantly wet and field capacity condition, on the other hand UJALA-14 gave better growth response under water stress conditions of ½ FC and ¼ FC when treated with FYM amendment. It is concluded that partial drought stress developed tolerance in wheat genotypes particularly in UJALA-14, which was strengthened with organic amendment. Combined use of drought tolerant varieties and application of FYM as a fertilizer is very effective way to enhance crop yield.

Soil aggregation in forest ecosystem is considered as a significant physical process mainly influenced by manure, fertilizers or combination. This aggregation may directly alter the soil nutrient and their fractions in soil. So, soil samples were collected from two types of forests i.e. Natural Korean pine forests (NKPF) and Korean pine plantation (KPP) in order to know the quantities of organic and inorganic Phosphorus (P) amounts in different aggregate sizes viz. >5 mm, 2–5 mm, 0.25–2 mm, 5 mm) and decreased with the decreasing aggregate size, while other variables, i.e., NaOH-Pi, NaHCO₃-Po, pH and T-N were not affected in aggregate size. H₂O-Pi (48 ppm), NaHCO₃-Pi (68 ppm), NaHCO₃-Po (80 ppm), NaOH-Po (623 ppm), HCL-Po (67 ppm), SOC (20.36 ± 1.6) was estimated in medium fertilizer treatment. PCA analysis showed that spread/variance of data points on F1 (62.90%) is more than spread/variance of data points on F2 (57.74%) in NKPF and KPP, respectively, while correlation matrix showed high correlation between H₂O-Pi and NaOH-Pi (0.63) and H₂O-Pi and NaHCO₃-Pi (0.63) while a strong negative correlation was present between Res-Pi and Po (−0.61). Moreover, litter inputs increased the organic-P fractions in soil particularly at medium treatment.