S. K. Bagchi , N. D. Dobriyal

Abstract

In a study of the Acacia nilotiea seed paramaters, provenance variation significant at 0.1% level of probability was observed. The estimates of provenance variation, residual variation and percentage of total variation explained by provenance revealed that the provenance were not able to explain tbe total variability more than 19%. This probably due to the musking effect of more number of samples from a particular zone on the others. The simple correlations between different pairs of characters were determined where length and width only were found to be correlated.

Full Text

     

M. A. Ram Reddy , S. N. Khan , N. D. Dobriyal

Abstract

The effect of mineral fertilizers and compost of the development of mycorrhiza in chir pine (Pinus roxburghii Sargent), an indigenous slow-growing pine and patula pine (P. patula Schlecht and Cham,) an exotic fast growing pine in India was studied. The effects or fertilizers and compost varied with the plant species, In chir pine, application of compost had better effect of plant growth except for reduction of short ischolar_mains but application of fertilizers reduced plant growth as well as short ischolar_mains. On the other hand, addition of compost had no effect on plant growth in patula pine but plant growth increases were directJy proportional to the dosages of NPK fertilizers. Both compost and fertilizers had no effect on short ischolar_main production. In both the species, mycorrhizal development was retarded by application of compost and high dosages of mineral fertilizers.

Full Text

     

B. K. Bakshi , N. D. Dobriyal

Abstract

The effect of several fungicides added to the soil to control damping-off disease in pines on the development of mycorrhiza was studied. All the fungicides had an initial retarding effect on mycorrhiza, particularly when the ischolar_mains were restricted within the treated zone. Mycorrhiza eventually developed in seedlings when their ischolar_mains penetrated beyond the treated zone, or when the toxic levels of chemicals were lowered in the treated zone in course of time. Adequate development of mycorrbiza resulted in healthy seedlings of Pinus patula with green lustre and better height growth over non-mycorrhizal seedlings which were pale and yellow.

Full Text