›› 2011, Vol. 54 ›› Issue (10): 1133-1139.doi:

• RESEARCH PAPERS • Previous Articles     Next Articles

Effects of seed wasps and seedless fruits on fruit and oil yields of Pistacia chinensis as a biofuel tree

 LIU  Qiong-Xia, WEN  Li-Zhang, ZHOU  Hua-Jian, WU  Qian, Marvin  K. HARRIS, XIAO  Zhi-Shu   

  • Received:4503-03-28 Revised:2011-08-21 Online:2011-10-20 Published:2011-10-20
  • Contact: XIAO Zhi-Shu
  • About author:liuqx0712@163.com

Abstract: Pistacia chinensis Bunge (Anacardiaceae) produces high-oil fruits and is being evaluated as an important biofuel source through establishing large plantations in China. However, harvest of fruit and oil crops from this tree may be limited by the damage from the seed wasp (Eurytoma plotnikovi Nikolskaya as the specialist seed predator) and seedless fruits (i.e., those parthenocarpic and aborted). In order to assess the impact of predator damage and seedless fruits on fruit and oil yields of this prospective biofuel tree, we quantified crop reduction caused by seedless fruits and seed wasps by estimating fruit and oil production among individual plants of three P. chinensis populations in Mt. Taihang Shan in Jiyuan City, Henan province and also measured fruit oil content for each fate category (i.e., sound, seedless and insect-infested). The results indicated that fruit conditions varied considerably both among individual plants and among populations with the average 53.0% exhibiting seedless fruits and 22.6% showing insectinfested fruits. The dry mass of either seedless (30.7 mg/fruit) or insect-infested (33.1 mg/fruit) fruits was less than half of sound fruits (67.4 mg/fruit), and the oil content was similar between deceptive (3.9%) and insect-infested (3.8%) fruits, but up to ten times lower than that (39.9%) of sound fruits. Based on dry mass and oil content for each fate category, the observed fruit yield (2.9 kg/tree) was reduced up to 50% of the expected (4.7 kg/tree), and the observed oil yield (0.6 kg/tree) was less than one third of the expected (1.9 kg/tree), and fruit and oil yields were similar among populations. Our study indicates that P. chinensis faces serious challenges posed by seedless and insect-infested fruits that need to be overcome before adopting this tree as a major biofuel source.

Key words: Pistacia chinensis, biofuel, biofuel tree, seed wasp, Eurytoma plotnikovi, seedless fruits, fruit yield, oil yield