Effect of cultivars and seed size on field performance of potato micro-tubers in North Eastern Himalayan region in India

Abstract

The present study was carried out at Central Potato Research Station, Shillong during 2013 and 2014 to assess the growth and yield performance of three grades of in-vitro produced micro-tubers viz. >8 mm, 4-8 mm and <4 mm of two potato (Solanum tuberosum) cultivars namely Kufri Girdhari and Kufri Megha under field planting conditions. The experiment was laid out in a randomised block design with four replications using a common spacing of 50 × 20 cm. The larger grade micro-tubers generally exhibited better physiological growth as well as yield parameters. The larger sized micro-tuber (>8 mm) showed significantly superior plant survival, canopy cover, plant height, number of compound leaves per plant, number of stems per plant and plant vigour followed by 4-8 mm grade and <4 mm grade micro-tubers. Similar trend was observed for all the yield parameters. Among varieties, Kufri Girdhari out performed Kufri Megha in all the growth and yield parameters in all the micro-tuber grades. Thus both micro-tuber size and genotype influenced the field performance. The overall finding indicates that micro-tubers irrespective of the size for both the varieties can produce mini-tubers successfully under direct field conditions in the NEH region which will facilitate quality seed production.

Effect of dormancy breaking chemicals on microtuber production potential under in vivo conditions of central India

“…Significantly higher stem/plant was recorded >8mm size microtubers (1.7) followed by >6-8mm size (1.2) over >4mm size microtubers (1.1) table 1. Present findings are also in agreement with Srivastava et al (2015) who reported that larger sized micro-tubers (>8 mm and 4-8 mm) did not exhibited significant (α = 5%) difference in terms of stems/plant but were superior to those in the smallest size microtuber (<4 mm). Number of compound leaves/plant at 50 days after planting were significantly higher at 5% level in 1ppm gibberllic acid+1% thiourea (12.1) followed by 1ppm gibberllic acid (11.9) over water control (8.8).…”

“…There was increase in plant height with increase in the GA 3 doses from 0 to 160 ppm in variety Morphona (Shekari et al, 2010) >8mm size microtubers (59.7 cm) at 75 days after planting. Increase in micro-tuber size from <4mm to >8mm size there was a corresponding increase in plant height when reported after 60 days after planting (Srivastava et al, 2015). This confirms the present findings of increase in plant height with increase in tuber size.…”

“…Microtuber emergence was showed decreasing trend with decrease size (Kawakami and Iwama, 2012). As the size grade decreases to <4 mm, the potential of the micro-tuber survival decreased significantly (79.4%) Srivastava et al (2015). Désiré et al (1995) The growth and survival/ vigor of potato tubers is supported by the food material stored in the tubers particularly carbohydrates and could thus be conducive to plant development and hence relatively bigger micro-tubers have distinct advantage as far as emergence is concerned and confirms the present study.…”

“…Microtuber using about 250-500 mg size is the best for maximizing minituber yield compared to plantlet may be a feasible practice under the field condition (Hossain et al, 2017). All the grades of micro-tubers (<4 mm, 4-8 mm and >8 mm) of both the varieties Kufri Megha and Kufri Girdhari were able to produce mini-tubers albeit with different efficiencies distinctly showing the effect of micro-tuber size and genotypes (Srivastava et al, 2015). Hence in the present investigation, an attempt was made to evaluate the effect of different dormancy breaking growth regulators and their dip duration on different grades of microtubers for growth and yield parameters under aphid proof net house conditions of central India.…”

Studies on microtuberization of five potato genotypes

“…Microtubers are more vigorous, easy to store and easier to handle comparing with in vitro plantlets Coleman, 1988 andMcCown& Joyce, 1991). Recently, many researches compared the performance of microtubers with traditional potato seed tubers and minitubers (Struik & Lommen, 1999, Wróbel, 2015and Srivastava, 2015. Furthermore, microtubers is used in potato seed production in many countries they improved self-sufficiency, reduce number of field generation and reduce disease frequency in the final product (Donnelly et al, 2003).…”