Irrigation Scheduling and Weed Management: A Sustainable Approach for Managing Broomrape and Other Weeds in Tomato Crop

Broomrape (Orobanche cernua L.) is an obligate root parasitic weed that significantly reduces the qualitative and yield attributes of tomatoes globally. The efficient management of broomrape is challenging because of its complicated parasitic nature. Field trials were conducted to assess the influence of various irrigation scheduling and weed control strategies on broomrape, weed presence, and tomato productivity. The experiment was conducted with a randomized complete block design (RCBD) with a split-plot arrangement and was replicated three times. Three irrigation intervals (3, 6, and 9 days) were assigned to the main block, while sub-blocks including treatments and year were taken as the source of variance (year × irrigation timing × treatments). The experiment comprised sixteen treatments, including transparent polythene, black polythene, weedy check (Control), sole weeding of broomrape only, weeding of all weeds, weeding except broomrape, humic acid 25 kg ha−1+ copper oxychloride in single and split doses, copper oxychloride (1.5 kg a.i ha−1 in single and split doses), ammonium sulphate 200 kg ha−1 in single and split doses, copper sulfate (2 kg ha−1 in single/split doses), and glyphosate 48 SL (1.5 kg a.i ha−1) and pendimethalin 33 EC (1.44 kg a.i ha−1). The results revealed that among the various irrigation intervals, the highest broomrape intensity (4.34 plant−1) was observed with a9-day irrigation interval. Similarly, the highest weed density (35 m−2) resulted in a3-day irrigation interval. Furthermore, irrigation at a 6-day interval increased the plant height by 11%, fruit yield tons ha−1 by 24.9 %, and produced the highest cost/benefit ratio (CBR) of (1:4). Black polythene, transparent polythene, and pendimethalin reduced the weed density by 92%, 89%, and 84%;weed dry biomass by 97%, 95%, and 91%; and broomrape intensity by 67%, 77%, and 28%. Conversely, the plant height increased by 24%, 23%, and 23.6%; and fruit yield by 286%, 270%, and 191%; and had the highest CBR of 1:5, 1:4, and 1:4, respectively, as compared to the weedy check. Consequently, an increase in irrigation frequency increases other weed densities and decreases the broomrape intensity plant−1 of tomato. Therefore, black polythene could be recommended in a severely broomrape-infested field. Moreover, irrigation at 6-day intervals combined with pendimethalin and ammonium sulfate fertilizers revealed the lowest incidence of broomrape and other weeds and produced an economic yield