Effects of mulching on plant growth, viral diseases, earliness and fruit yield attributes of round gourd under variable sowing dates in North Indian plains

Abstract

Round gourd is sensitive to low temperature (March), high temperature (May–June), high humidity (July–August), and whitefly-transmitted begomovirus diseases (July–September), thereby restricting its fruit availability period in North-Western Indian Plains. Mulches extend the growing season by modifying soil temperature and reducing the incidence of viral diseases. Therefore, the present study was conducted to investigate the effects of sowing time, mulching and their interaction on performance of round gourd crop so as to identify the best mulch at different sowing times. The field trials were conducted in a split-plot design during 2021 and 2022. The main plot consisted of six sowing dates, i.e., the first week of March (DS1), April (DS2), May (DS3), June (DS4), July (DS5) and August (DS6). The sub-plot comprised bare soil (BS) and three mulching treatments, viz., silver-black plastic mulch (SBPM), black plastic mulch (BPM) and paddy straw mulch (6 t/ha) (PSM). The BPM and SBPM increased the seasonal soil temperature over BS by 3.1–4.1°C and 2.1–3.1°C, respectively, whereas the PSM reduced the seasonal soil temperature by 2.3–3.5°C. The SBPM produced the best crop performance, followed by BPM and PSM in all sowing dates except DS5 in which the PSM outperformed BPM. The DS1 and DS2 were the best sowing times, and the crop performance gradually declined with each successive sowing time, except that the crop performed better in DS6 compared with DS5. The SBPM or BPM in DS2 and DS1 were the best treatment combinations for round gourd cultivation in the study area.