THE INFLUENCE OF CLADODE MORPHOLOGY ON THE CANOPY FORMATION OF FORAGE CACTUS PLANTS

ABSTRACT Here we aimed to evaluate the influence of cladode morphology on the canopy formation of forage cactus plants. The study was carried out in Serra Talhada, the State of Pernambuco, using the IPA Sertânia (IPA), Miúda (MIU), and Orelha de Elefante Mexicana (OEM) clones, which were submitted to three irrigation depths (2.5, 5.0, or 7.5 mm) and three irrigation intervals (7, 14, or 28 days) from March 2012 to August 2013. Cladode and plant canopy biometric data were obtained during the experimental period. We found that the characteristics of the second and third order cladodes contributed most to the canopy formation of clones of the genus Nopalea (IPA and MIU), whereas, for the genus Opuntia (OEM), the first and third order cladodes contributed most. Overall, we found that the influence of the cladode variables on the canopy growth of forage cactus is more associated with the characteristics of the genus than to the peculiarities of the clones.

摘要：本研究旨在评估肉质茎（cladode）形态对饲用仙人掌（forage cactus）植株冠层形成的影响。实验于巴西伯南布哥州塞拉塔尔哈达（Serra Talhada）开展，供试材料为IPA Sertânia（IPA）、Miúda（MIU）及Orelha de Elefante Mexicana（OEM）三个克隆品系，实验周期为2012年3月至2013年8月，设置3个灌溉深度（2.5、5.0或7.5 mm）与3个灌溉间隔（7、14或28天）。实验期间采集了肉质茎与植株冠层的生物测量数据。研究结果表明，第二、三级肉质茎的特征对Nopalea属（IPA与MIU）克隆的冠层形成贡献最大；而对于Opuntia属（OEM），第一、三级肉质茎的特征贡献更为显著。综合分析可知，肉质茎相关变量对饲用仙人掌冠层生长的影响更多与物种所属的属特征相关，而非不同克隆的特异性。