Production Of Potato (Solanum Tuberosum L) Pre-Basic Seed Through Tissue Culture In Katibougou, Mali

ABSTRACT In Mali, the main problems limiting the productivity and production of potatoes is the nonavailability of quality seeds in adequate quantities and at affordable prices for the farmers. To meet quantity and quality requirements for potato seeds in Mali, this study proposes to undertake two experiments to improve the techniques adopted in the IPR/IFRA plant biotechnology laboratory in Mali. The evaluation of the effects of three (3) concentrations of coconut water and two (2) concentrations of potassium nitrate on potato plantlets growth in vitro and the effects of two physiological ages and three substrates on potato in vitro plants’ establishment, post in vitro growth and mini tubers production in vivo. The first experiment was laid out in a Completely Randomized Design (CRD) with twelve (12) treatments replicated 4 times. The second experiment was a factorial experiment with 2 factors (physiological ages: 2 levels and substrate: 3 levels) laid out in a Randomized Complete Block Design (RCBD) with 6 treatments replicated 4 times. The results in the first experiment showed that the culture medium M7 (MS+40 ml/l of coconut water +250 mg of potassium nitrate) had promoted all plant growth parameters (shoot emergence, plant height, number of nodes, leaves and roots and plant fresh and dry weight) after 30 days of in vitro culture. The lower concentrations of coconut water (40 ml) and potassium nitrate (250 mg) per liter of MS medium had significant and positive effects on all the in vitro growth parameters after 30 days of culturing. The results in the second experiment showed that the plantlet weaning age of 25 days and the post-flask culture substrate S1 (only soil) provided the best plant survival percentage at 20 days after transplanting in vivo. The substrate S2 (soil and cow dung 2:1) positively affects plant stem length, stem diameter, plant fresh and dry biomass formation, tuber yield, tuber numbers per plant and tuber grading size B (tubers with a diameter of less than 28 mm). The substrate compositions S1(only soil) has significantly affected the weight loss (12.50%) of v tubers stored within 8 weeks. The weaning age 45 days and the substrates S2 (soil and cow dung 2:1) and S3 (soil and cow dung 1:1) conditions significantly reduced the number of sprouts per tuber and sprouts number per eye on tubers. In addition, the results indicate that for better and more rapid growth of potato plantlets in vitro culture, the coconut water concentration used as supplement to MS medium should be 40ml per liter of medium. The proportion of cow dung used in substrate composition should not exceed the soil and cow dung 2:1 mixture for maximum post transplanting plant reestablishment rate in vivo and for rapid maturity of mini-tubers.