Programa de Pós-Graduação em Botânica, Universidade Federal Rural de Pernambuco, Recife, Brazil.
Universidade Estadual de Alagoas, Campus III, Palmeira dos Índios, Brazil.
Plant Biol (Stuttg). 2019 Jan;21(1):142-149. doi: 10.1111/plb.12910. Epub 2018 Oct 23.
Loss and fragmentation of native vegetation negatively affect crop pollinators and productivity of several crop species. The yellow passion fruit is an excellent model to investigate this issue, because its main pollinators are sensitive to deforestation. Seasonality also influences fruit set of crop species that are pollinated by bees. Climate determines plant flowering patterns and consequently affects pollinator activity. Little is known on effects of pollinators on crop quality in general, and particularly of many tropical fruits that have multiple fruiting seasons throughout the year, such as passion fruit. Our hypothesis is that the distance to the native vegetation and climate seasonality affect the pollination and fruit production of cultivated, hermaphrodite, self-incompatible, protandrous species that depend on large-sized bees to set fruit. We observed flowers of the yellow passion fruit in eight areas at different distances (600-4,000 m) from a dry seasonal forest (Caatinga). We compared the frequency of the main floral visitor (pollinators and robbers) visits and fruit set among areas at the beginning and end of the dry and rainy seasons. Xylocopa species were pollinators, and Apis mellifera, Trigona spinipes and a hummingbird were robbers. Xylocopa visits diminished with increasing distance to native remnants, converse to what was observed for the robbers at the beginning of the dry season. Fruit set was higher at the beginning of the dry season. The distance to the forest affected quality of fruits in terms of length, diameter and skin thickness, which all decreased with increase in remnant distance. Our results show that insect pollination is higher in the dry season, increasing profitability and reducing labour costs for the producer. Considering the influence of distance to native vegetation on pollination, robbery and fruit quality, our study reinforces the necessity for conservation of native vegetation remnants.
原生植被的丧失和破碎化会对作物传粉者和几种作物的生产力产生负面影响。黄百香果是研究这一问题的理想模型，因为它的主要传粉者对森林砍伐很敏感。季节性也会影响蜜蜂授粉的作物的结实率。气候决定了植物的开花模式，从而影响传粉者的活动。关于传粉者对作物质量的影响，人们知之甚少，特别是对许多热带水果，它们全年有多个结果季节，如百香果。我们的假设是，与原生植被的距离和气候季节性会影响依赖大型蜜蜂来结实的栽培、雌雄同体、自交不亲和、先熟型物种的授粉和果实生产。我们在距离一个季节性干燥森林（卡廷加）不同距离（600-4000 米）的八个区域观察了黄百香果的花朵。我们比较了在旱季和雨季开始和结束时，不同区域主要花卉访客（传粉者和掠夺者）访问频率和结实率。黄木蜂是传粉者，而西方蜜蜂、三叶木蜂和蜂鸟是掠夺者。随着与原生植被距离的增加，黄木蜂的访问量减少，与旱季开始时掠夺者的情况相反。旱季开始时果实结实率较高。森林的距离影响果实的质量，表现为长度、直径和果皮厚度，随着残体距离的增加而降低。我们的结果表明，昆虫授粉在旱季较高，提高了生产者的盈利能力并降低了劳动力成本。考虑到与原生植被距离对授粉、掠夺和果实质量的影响，我们的研究强调了保护原生植被残体的必要性。
