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Tomato (Lycopersicon esculentum Mill; Solanaceae) is one of the major horticultural crops cultivated in India. In order to ensure year-round availability of tomatoes, farmers are shifting to protected cultivation practices. Although the name ‘protected cultivation’ suggests freedom from biotic as well as abiotic hindrances in crop cultivation, incidence of pests have been reported in crops grown under polyhouses. This causes net house cultivators to use more chemical insecticides. Thus, an environmentally safe and economical method, comprising sticky traps, was evaluated for the management of sucking pests of tomato grown under protected conditions. Sticky traps of different shapes (rectangle, circle and triangle) and colours (yellow, blue and silver) were evaluated against sucking pests of tomato in 2018. The sticky trap, which found most efficient during 2018, was installed at different rates (2, 4 and 6 traps/250 m2) in the year 2019. Among the various sticky traps evaluated, yellow colour and rectangular trap proved best among the other shapes and colours against the aphids and whiteflies infesting tomato under protected conditions. On standardization of yellow-rectangular trap in 2019, a rate of installation of 4, 6 and 2, 4, 6 traps per 250 m2 were effective in reducing the population of aphids and whiteflies, respectively. Hence it could be concluded that yellow-rectangular sticky trap installed at a rate of 4 per 250 m2 proved effective against sucking pests of tomato grown under protected conditions.

Funder: Helmholtz-Zentrum Potsdam Deutsches GeoForschungsZentrum - GFZ, National Capital Region (NCR, Delhi) in India is one of the fastest-growing metropolitan cities which is facing a severe water crisis due to increasing water demand. The over-extraction of groundwater, particularly from its unconsolidated alluvial deposits makes the region prone to subsidence. In this study, we investigated the effects of plummeting groundwater levels on land surface elevations in Delhi NCR using Sentinel-1 datasets acquired during the years 2014-2020. Our analysis reveals two distinct subsidence features in the study area with rates exceeding 11 cm/year in Kapashera-an urban village near IGI airport Delhi, and 3 cm/year in Faridabad throughout the study period. The subsidence in these two areas are accelerating and follows the depleting groundwater trend. The third region, Dwarka shows a shift from subsidence to uplift during the years which can be attributed to the strict government policies to regulate groundwater use and incentivizing rainwater harvesting. Further analysis using a classified risk map based on hazard risk and vulnerability approach highlights an approximate area of 100 square kilometers to be subjected to the highest risk level of ground movement, demanding urgent attention. The findings of this study are highly relevant for government agencies to formulate new policies against the over-exploitation of groundwater and to facilitate a sustainable and resilient groundwater management system in Delhi NCR.

Pest infestations in net-houses are not sometimes different from that under open-field conditions, necessitating usage of pesticides. To examine the hypothesis that bioagents may have more potential under restricted plant growing conditions, the predatory potential of green lace wing, Chrysoperla zastrowi sillemi Esben-Peterson (Neuroptera: Chrysopidae) was evaluated against the sucking pests of tomato under screen-house conditions. The rates of release were fixed as 4, 5, and 6 s instar grubs plant−1 and a total of 3 releases were made at 7 days interval, with first release at appearance of the aphid, Myzus persicae (Sulzer) and whitefly, Bemisia tabaci (Gennadius). The pooled data for the years 2018 and 2019 revealed that, the release rates 4, 5, and 6 grubs plant−1 were not statistically different in reducing the population of these pests. The factorial analysis based on the release rate and time of these releases suggested that single release of C. zastrowi sillemi at 4 grubs plant−1 was effective against sucking pests in tomato grown under screen-house conditions.