Orthogonal test design for optimizing culture medium for in vitro pollen germination of Chinese chinquapin (Castanea henryi)

2018 Taiwan Forestry Research Institute. All rights reserved. Chinese chinquapin (Castanea henryi (Skam) Rehder & Wilson) is an ecologically and economically important nut tree species in southern China. Chinquapin suffers from high rates of empty shells, which are directly related to low pollination efficiency. Efficient pollination mainly depends on pollen vigor, which depends on the pollen grain germination rate and the rate of pollen tube growth. We studied the pollen germination rate and pollen tube length of the advanced chinquapin cultivar HCHJA-1; specifically, we compared the effectiveness of different concentrations of 3 key factors by an orthogonal design method: Boric acid (H3BO3), calcium chloride (CaCl2), and gibberellic acid (GA3), to determine pollen vigor and optimize the culture medium for in vitro pollen germination. Results indicated that chinquapin pollen germination rates were significantly affected by medium components. The pollen germination percentages varied between 13.02 and 66.99%. Three factors influenced pollen germination in the order of decreasing significance: GA3 H3BO3 CaCl2. Pollen tube growth was influenced by these factors as follows: H3BO3 GA3 CaCl2. The optimal culture medium for promoting pollen vigor of C. henryi HCHJA-1 was 1% agar, 10% sucrose, 20 mg L-1 GA3, 100 mg L-1 H3BO3, and 50 mg L-1 CaCl2.

Orthogonal test design for optimizing culture medium for in vitro pollen germination of Chinese chinquapin (Castanea henryi) Academic Article