Population Density of Major Insect Pest as Influenced by Spatial Arrangement in Pechay
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population density of major insect pest as influenced by spatial arrangement in pechay
Spatial arrangement in pechay production could be used as an strategic pest management. Three different spacing were used to determine the effects of spatial arrangement in the population density of pechay. The spacing were 2.5 x 5 in, 3.5 x 5 in and 5 x 5 in per plant. Collections of insect pests were done starting five days after transplanting and continued every three days until harvest. Damage rating and yield were also measured. The spacing of 5 x 5 in per plant significantly affected the lowest incidence of insect pest, leaf damage and with highest yield. The 5 x 5 in spacing per plant in this study could thus help reduce incidence…show more content… It is used as main ingredient for soup and stir-fried dishes. In Chinese cuisine, its green petioles and leaves are also used as garnish
Damping-off, soft rot and clubroot are the most important diseases of pechay, while diamondback moth and aphids are the major insect pests Plutella xylostella (Linnaeus)
On a per larva basis, the diamondback moth causes less damage than the other two species, however, populations can be high enough to cause severe damage.
Crop damage is caused by larval feeding. First instars mine leaf tissue, thereafter feeding occurs on the undersurface of the leaf, resulting in a windowpane from the remnants of the top leaf surface. The windowpane will dry, crack and fall out over time. Pupation lasts 5-15 days in a loose silk cocoon. Total development from egg to pupal stage ranges from 17-51 days, and averages 25-30 days.
Rainfall is a useful mortality factor. Rainfall, and sprinkler irrigation, kills young larvae. Drip or furrow-irrigated crops tend to have higher populations.
Row covers, when placed on the crop prior to immigration of any life stage, are an effective control.
The sex pheromone used by females to call in males is known and available commercially for monitoring. It is a good management practice to put several pheromone traps in each field, to help you know when moths are flying. At a higher concentration and distribution, scientists are experimenting with the sex pheromone to disrupt mating, with some notable success in