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Potato (Solanum tuberosum ssp. tuberosum) cultivars grown under tropical conditions exhibit comparatively poor yields compared to the temperate conditions, hence, there is need for stable cultivars with greater yields. The interactions of four cultivars with ten environments for 2 years under All India Coordinated Research Project (Potato) across the country for 2 harvesting stage (75 and 90 DAP) revealed that the cultivars were significantly different among themselves for Total Yield (TY) and Marketable Yield (MY) harvested at 75 and 90 DAP at seven and eight environments, respectively. The pooled analysis showed a significant difference for cultivar and environmental main effects for all traits, indicating the existence of cultivars genetic variability justified from the heterogeneity of environments. The significant effect of G×E interaction for TY and MY at 90 DAP, and a non significance for the same traits at 75 DAP clearly indicated that the prevailing environments during early crop stage were uniform as compared to its later harvesting stage. Partitioning of G×E interaction into linear and non linear components were highly significant for all traits, strongly suggesting the real differences in cultivars for regression over environmental means and the response of cultivars to environment was controlled genetically. The cultivar K. Pukhraj was proven as early bulking and stable cultivar for TY and MY at 75 DAP and predictable in nature, as against K. Khyati which was stable cultivar for TY and MY at 90 DAP across growing environments. Hence, K. Khyati, which recorded the highest TY (27.45 t ha^-1) and MY (25.24 t ha^-1) for harvesting at 75 DAP, and TY (31.28 t ha^-1) and MY (28.19 t ha^-1) at 90 DAP, can be recommended for tropical conditions.

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Tubers of the tuberous orchids have been col­lected for centuries, and used for medicinal purposes as well as in beverage and ice-cream industry. These orchids (Sahlep orchids) cannot be propagated vegetatively as they generally do not yield more than one tuber in a year. Seeds do not have microscopic endosperms; they have quite small chance of germination and successful establishment. These orchids are not cultivated and are usually collected from natural populations. Therefore, they are under threat of extinction and thus are placed under protection worldwide with national and international treaties. In this study, specimens of the threatened orchid taxa Ophrys sphegodes subsp. mammosa (Desf.) Soo ex E. Nelson orchid, were stimulated to grow tuber twice in a single vegetation period. Plants’ ability to develop new tubers was tested and a new propagation method was proposed for the first time worldwide. Plants harvested at the beginning, middle, and end of flowering period were re-planted. It was observed that the plants harvested at early flowering were able to develop new tubers when they were re-planted in their original places. At the end of their annual life cycle, the number of tubers that were produced by the plants harvested at the three subsequent harvest periods were 2.21, 2.10, and 1.04. Quality of the tubers of the 2^nd harvest was also tested in this study to use them as propagation material for the subsequent season, and positive outcomes were achieved. According to the present findings, growth of two tubers in a single vegetation period was achieved for the first time. Possible sustainable cultivation of Sahlep orchids was proved by this new propagation method.