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Indian gooseberry, popularly known as amla, is harvested from two species of Phyllanthus, namely Phyllanthus emblica and Phyllanthus indofischeri. Although these two species are characterized on vegetative and reproductive features, development of reliable and authentic identification based on molecular approaches is necessary for precise identification. Most of the commercial orchards of Indian gooseberry are established with mixture of the two species. Introduction of unauthentic clones and seedlings in the establishment of orchards and differences in the growth of these two species under different elevations are the major constrains in identification. The present work aims to study the changes in vegetative and reproductive features under different elevations and to develop a simple molecular tool for precise identification of these two species based on single nucleotide polymorphisms in trnL (UAA) intron sequences of chloroplast DNA. Genomic DNA of leaf tissues of P. emblica and P. indofischeri, collected from the authentic source, was subjected to polymerase chain reaction amplification using trnL (UAA) intron gene-specific primers. The amplified product with the molecular weight of 540 bp was sequenced and used as reference for identification of these two species. The trnL (UAA) introns sequenced from 60 individual trees in three different orchards were compared with trnL (UAA) intron of authentic samples, and confirmed that these orchards have 76% population of P. indofischeri and remaining 24% is occupied by P. emblica. Thus, trnL (UAA) intron is a potential DNA marker for precise identification of these two species. The importance of the present study and its practical application in genetic improvement of Indian gooseberry are discussed.

Cytological examination of anther-culture-derived plants of rice showed that the regenerants were predominantly diploids and haploids. Haploid meiosis indicated that the earlier hypothesis of rice being an ancient polyploid is unlikely. Diploids generally were normal and fertile. The low frequency of polyploids (1.5%) probably was due to rapid regeneration of plants from short term callus cultures.

Effect of position of anthers at plating in relation to their ability to form callus was studied in rice (Oryza sativa var. Taipei 309). Among the callusing anthers, about 60% were those positioned on edge with one lobe in contact with the medium while the rest were flat with both lobes touching the medium. Anthers in both positions produced calli and regenerated green plants.

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