Agronomic Components in IPM
Agronomic adjustments, necessary for higher yields, are at the same time are directed at preventing mass multiplication and spread of pest, diseases and weeds by modifying the crop micro climate, following are the important Agronomic components of IPM.
Ploughing brings about unfavorable condition for multiplication of pests, diseases and weeds inhibits the soil Pupae of harmful organism will be exposed to dehydration or to predation by birds and other stages may be mechanically damaged or buried deep in the soil. Summer ploughing ploughing produces the presence of several pests.
Cultivars with high yield potential and quality without resistances to pest and disease are the main cause of tolerate to pest and diseases have been developed. Selection of such Cultivars can bring down the pest and disease incident considerably.
Time Of Sowing:
As weather influence developmental rhythm of plants as well growth and survival old pest and disease, serious setback occurs when the weather condition are such as to bring about coincidence of the susceptible crops stages with highest incidence of pests and disease, therefore, adjustments in sowing time is often restored to an agronomic strategy to escape the crop loss. In general early sowing in the season concidrly reduces the pest and disease attack.
Plant population per unit area influence crop microclimate. Dence population restrict wind movement within plant canopy leding to high humidy build up. This creates congenial condition for pest and disease multiplication. Keeping the plant population constant, inter and intra row plant population can be adjusted to minimize the humidity buildup within the crop canopy.
Mechanical or manual Intercultivation suppresses the pest, diseases and weeds to that of preparatory tillage, weeds that could serve as alternate host to insect and pathogen can be efficiently controlled with Intercultivation, microclimate conductive to pest and disease buildup will be distubuted by Intercultivation.
Manures and Fertilizers:
Excessive nitrogen application increases susceptibility of crop to sucking and leaf eating pests because of the succulence to the crop conferred by nitrogen. High rates of nitrogen than the recommended rate to hybrids without corresponding increase in phosphorous and potassium is the main factor for heavy pest and disease incidence. It is know that balance fertilizer application helps the crop to tolerate pest and diseases considerably.
Irrigation and Drainage:
Modification of natural water supply changes the biological equilibrium between crop and its pest and disease. Irrigation can reduce the soil inhabiting pests by suffocation or expositing them to soil surface to be preyed upon by birds. Granular insecticide and herbicide applied in the soil do not become available until dissolved in the water. Systemic chemical are not absorbed by plants in the absence of adequate soil moisture. Water logged or saturated soils create microclimate on the crop productive to building pest and disease.
Advantages of crop rotation have been well known to us. It serves the purpose of palnt protection by reducing the nutrition of pests in every subsequent year or season or totally deprives them of food. It reduces the amount of initial infection by diseases and ensure unfavorable stratum for its development.