Soil quality under different land uses in eastern India: Evaluation by using soil indicators and quality index.

Indian soils are inherently poor in quality due to the warm climate and erosion. Conversion of land uses like forests to croplands and faulty management practices in croplands further cause soil degradation. This study aimed to understand the extent of these impacts in a small representative part of eastern India, covering Himalayan terai and nearing alluvial plains. Soils were collected from (i) forests, (ii) croplands (under agricultural practices for more than 50-60 years) and (iii) converted lands (converted from forests to croplands or tea gardens over the past 15-20 years). Different soil quality indicators were assessed and soil quality index (SQI) was generated to integrate, scale and allot a single value per soil. Results indicated that continuous organic matter deposition and no disturbances consequence the highest presence of soil carbon pools, greater aggregation and maximum microbial dynamics in forest soils whereas high application of straight fertilizers caused the highest available nitrogen and phosphorus in cropland soils. The SQI scorebook indicated the best soil quality under forests ([Formula: see text] 0.532), followed by soils of converted land ([Formula: see text] 0.432) and cropland ([Formula: see text] 0.301). Comparison of the SQI spatial distribution with land use and land cover confirmed the outcome. Possibly practices like excessive tillage, high cropping intensity, no legume in crop rotations, cultivation of heavy feeder crops caused degraded soil quality in croplands. This study presented an example of soil quality degradation in India due to land use change and faulty management practices. Such soil degradation on a larger scale may affect future food security.

Seed priming with non-ionizing physical agents: plant responses and underlying physiological mechanisms.

Seed priming has long been explored as an effective value-added potential technique that results in improved germination, reduced seedling emergence time, shortened crop duration, increased stress tolerance and eventually increased higher grain production. However, the wider applicability of water or chemical-based conventional methods of seed priming is often restricted considering its deleterious effects on post-treatment storability or agricultural pollution due to the persistence of chemicals in plant systems or in the environment. In this context, the utilization of physical methods of seed priming for enhancing plant productivity has created a new horizon in the domain of seed technology. Being eco-friendly and cost-effective approaches, priming with extra-terrestrial or physical agents such as ionizing radiation such as X-rays and gamma rays and non-ionizing radiation such as ultrasonic wave, magnetic field, microwaves, and infrared light offers many advantages along with ensuring enhanced production over conventional methods. Ultraviolet radiations, bridging between ionizing and non-ionizing radiation, are important electromagnetic waves that would also be an effective priming agent. Non-ionizing radiation has certain biological advantages over ionizing radiation since it does not generate charged ions while passing through a subject, but has enough energy to cause biological effects. Extensive research works to study the effects of various non-ionizing physical priming methods are required before their wider exploitation in agriculture. With this background, this review aims to highlight the current understanding of non-ionizing physical methods of seed priming and its applicability to combat present-day challenges to achieve agro-ecological resilience.