EFFECT OF MICRONUTRIENT APPLICATION ON THE GROWTH AND OCCURRENCE OF STERILITY IN BARLEY AND RICE IN A MALAYSIAN DEEP PEAT SOIL

In order to elucidate the cause of poor growth and occurrence of sterility observed in crops cultivated in a Malaysian deep peat soil in the absence of micronutrient application, the growth and performance of barley and rice were investigated. The results obtained were as follows: (1) Cu and B were the most deficient micronutrients in this peat soil. In barley, the absence of Cu resulted in very poor shoot growth and no grains were formed. In the absence of B, shoot growth was most active with an extremely large number of tillers but grain formation was nil. In rice, the growth response to the absence of Cu and B was essentially similar to that of barley but sterility occurred only in the -Cu treatment. The occurrence of sterility in barley was mainly attributed to the lack of Cu and B while the sterility in rice was mainly attributed to the lack of Cu only. (2) In the absence of Mo, the sterility percentage was slightly higher than that of the complete treatment, presumably due to the acceleration of tiller development during the later growth stage.