RESPONSE OF BITTER GOURD (Momordica charantia) TO CULTURAL AND CHEMICAL WEED CONTROL METHODS
Experiments were conducted at the farm of the University of Agriculture Peshawar in 2012 and 2013 to evaluate the effect of different weed control methods in bitter gourd. The treatments comprised of four mulches (Rumex crispus, Silybum marianum, news papers, and saw-dust), a herbicide i.e. Stomp 330 EC (pendimethalin) applied as pre-emergence, a hand weeding and a control treatment (weedy check). Data were collected on weed biomass, number of plants ha-1 and fruit weight. The parameters were significantly affected by the applied treatments during both the years. Weed biomass in 2012 and 2013 was the highest (2971 and 3595 kg ha-1, respectively in the weedy check treatments and lowest in hand weeded plots (68 and 83 kg ha-1) in 2012 and 2013, respectively. Moreover the effect of the mulching treatments and the herbicide treatment were statistically at par with each other and different from the weedy check. The highest number of plants ha-1 (9773 and 8077) and fruit weight plant-1 (756 and 657 g) were recorded in the hand weeded treatments in 2012 and 2013, respectively. Hand weeding was followed by the treatment of Stomp 330 EC with the respective values in the two years as 8834 and 7301 plants ha-1, and 667 and 580 g plant-1 in 2012 and 2013, respectively. Moreover, the performance of the mulching treatments was also significantly more effective than the weedy check plots. Mulches of S. marianum and R. crispus reduced the weed biomass to 1072 and 1615 kg in 2012 and 1297 and 1954 kg in 2013 as compared to the weedy control with weed biomass of 2971 and 3595 kg ha-1 in 2012 and 2013, respectively. The respective no. of plants ha-1 for the mulches of S. marianum and R. crispus were 8548 and 8489 in 2012 and 7065 and 7016 in 2013 whereas and the fruit weight plant-1 was 435 and 396 in 2012 and 378 and 344 g in 2013. Keeping in view the good performance of weed biomass as mulches, the cost of production and the environmental safety, the hand weeding and herbicide use cannot be preferred alone for use as weed management tools. Therefore, the herbicide use and hand weeding should be used only on casual basis or in emergency; and the mulching methods should be adopted in the long run as mulching method is not only good for weed control but also for maintaining the soil fertility, moisture conservation, and environmental safety.