Agro-management practices for enhanced productivity in canola (Brassica napus L.)

Two sets of field experiments were conducted. In the first experiment effect of different N P and K levels on the growth and yield content of canola (Brassica napus L.) was studies. For that two field experiments with ten treatments and three replications were conducted during 1999-2000 and 2000- 2001 seasons. The N, P and K levels consisted of 0-0-0, 50-0-0, 0-30-0, 50-30- 0, 50-30-50, 100-30-50, 100-60-50, 100-90-50, 100-90-100 and 150-90- 100 kg ha- 1 respectively. Plot size was 2.4 m x 5.1 m. Crop was sown in paired row strips (60/20 cm), with plant to plant distance of 15 cm. In both seasons, the leaf area index (LAI) was significantly influenced by increasing N, P and K applications. Maximum LAI value was achieved by treatment T10. Various yield components such as plant height, number of pods plant-1, seeds pod-1 and 1000-seed weight were affected significantly - by different levels of N, P and K. The highest seed yield was obtained in treatment T7 (100-60-50 kg NPK ha- 1) which may be due to optimum growth resulting in improvement in components of yield. The number of pods plant-1, seeds pod-1, and average seed weight were greater in T7 than all other treatments. Seed protein contents were enhanced with increasing levels of N, P and K (especially N rates). Significant decreases in oil contents with increasing rates of fertilizer application (especially N) reflects an inverse relationship between oil concentration and seed protein contents. The higher oil yields in treatments T6, T7, T8 and T9 was due to their higher seed yield. Results of this study suggest that high seed and oil yield and greater economic benefit will be obtained under Faisalabad conditions when a canola crop is fertilized @ 100- 60-50 kg NPK ha-1. In the second experiment Production potential and net income of different canola Brassica napus L.)-based intercropping systems was studies. Two field experiments with nine treatments and three replications were conducted. The experiments were laid out in a randomized complete block design (RCBD). Net plot size was 2.4 m x 5.1 m. The intercropping systems were no intercropping (sol canola + one row of wheat, canola + two rows of wheat, canola + one row of gram, canola + two rows of gram, canola + one row of lentil, canola + two rows of lentil, canola + one row of linseed and canola + two rows of linseed. Canola was sown in 60 cm spaced paired row strips (60/20 cm). Each intercrop was also sown as sole crop to calculate competition functions and agronomic advantages. All the intercropping systems gave higher net field benefits than -that of the monocropping of canola except canola + two rows of gram canola + one row of lentil. All associated cultures reduced canola yield to a significant extent in both the years. However, the additional harvest obtained from the associated crops compensated more than the losses in canola production. The various yield components of canola, as number of pods plant-1, seeds pod-1 and 1000-seed weight, were affected significantly by different intercropping systems. Leaf area index (LAI) and crop growth rate ;(CGR) of canola were reduced due to intercropping of wheat and linseed compared with sole canola. Different intercropping systems gave considerably higher yields compared to monocropped canola in terms of canola seed-yield equivalent (CSYE). The highest CSYE was recorded for canola + one row of wheat against the minimum for sole canola. The canola + one row of wheat intercropping system showed the highest yield advantage of 24 and 16 percent in terms of LER and ATER respectively, followed by canola + two rows of wheat. Among the component crops, canola appeared to be the dominant crop as indicated by higher values of relative crowding coefficient and competitive- ratio, as well as a positive sign of the aggressively values. This suggests that canola grown in association with wheat, gram, lentil, and linseed utilized the resources more aggressively than the respective intercrops which Appeared to be dominated. Wheat, grain, lentil, and linseed produced substantially smaller yields when grown in association with canola compared to their monocultures: Among all the intercropping systems- under study, canola + one row of wheat proved to be the best one as it gave higher NFB ha. In conclusion, the results suggest that higher seed yield an greater economic benefit will be obtained under Faisalabad conditions when the canola crop is fertilized @100-60-50 kg NPK ha-1. Moreover, for achieving the maximum yield advantages and net income ha-1. Canola should be intercropped, with one row of wheat under the planting pattern of 60 cm spaced paired row strips (60/20 cm).