Impact of water deficit on the development and senescence of tomato roots grown under various soil textures of Shaanxi, China.

purposeWater scarcity is expected to extend to more regions of the world and represents an alarming threat to food security worldwide. Under such circumstances, water holding capacity is an important agronomic trait, which is primarily controlled by soil texture.

methodsOur work examined three different soil textures from three cities of Shaanxi Province in China, i.e., silt-sandy loam from Yulin (north of Shaanxi), loam-clay loam from Yangling (middle and western part of Shaanxi), and clay loam-clay from Hanzhong soil (south of Shaanxi), at two moisture levels, i.e., field capacity of 70-75% (well-watered) and 50-55% (water deficit).

resultsThe differences in soil particle sizes altered the soil physiochemical properties and soil enzymatic activities. Soil urease and ß-glucosidase activities were significantly higher in the Yangling soil under the well-watered treatment, while the differences were nonsignificant under the water deficit conditions. The leaf photosynthesis rate and total chlorophyll content were significantly higher in Hanzhong soil after 15 days of treatment; however, the overall highest plant length, root cortex diameter, and xylem element abundance were significantly higher in Yangling soil under the water deficit conditions. Furthermore, comparable differences were observed in antioxidant defence enzymes and endogenous hormones after every 15 days of treatments. The auxin, gibberellic acid and cytokinin concentrations in leaves and roots were comparably high in Yangling soil, while the abscisic acid concentrations were higher in Hanzhong soil under the water deficit conditions.

conclusionsOur findings concluded that soil compaction has a significant role not only in root morphology, growth, and development but also in the soil physicochemical properties and nutrient cycle, which are useful for the growth and development of tomato plants.