Table_1_Genotypic and Environmental Effects on Morpho-Physiological and Agronomic Performances of a Tomato Diversity Panel in Relation to Nitrogen and Water Stress Under Organic Farming.XLSX

The agricultural scenario of the upcoming decades will face major challenges for the increased and sustainable agricultural production and the optimization of the efficiency of water and fertilizer inputs. Considering the current and foreseen water scarcity in several marginal and arid areas and the need for a more sustainable farming production, the selection and development of cultivars suitable to grow under low-input conditions is an urgent need. In this study, we assayed 42 tomato genotypes for thirty-two morpho-physiological and agronomic traits related to plant, fruit, and root characteristics under standard (control) and no-nitrogen fertilization or water deficit (30% of the amount given to non-stressed trials) treatments in two sites (environments), which corresponded to organic farms located in Italy and Spain. A broad range of variation was found for all traits, with significant differences between the applied treatments and the cultivation sites. Dissection of genotypic (G), environmental (E), and treatment (T) factors revealed that the three main factors were highly significant for many traits, although G was the main source of variation in most cases. G × E interactions were also important, while G × T and E × T were less relevant. Only fruit weight and blossom end rot were highly significant for the triple interaction (G × E × T). Reduction of water supply significantly increased the soluble solid content in both locations, whereas both nitrogen and water stress led to a general decrease in fruit weight and total yield. Despite so, several accessions exhibited better performances than the control when cultivated under stress. Among the accessions evaluated, hybrids were promising in terms of yield performance, while overall landraces and heirlooms exhibited a better quality. This suggests the possibility of exploiting both the variation within ancient varieties and the heterosis for yield of hybrids to select and breed new varieties with better adaptation to organic farming conditions, both under optimal and suboptimal conditions. The results shed light on the strategies to develop novel varieties for organic farming, giving hints into the management of inputs to adopt for a more sustainable tomato cultivation.

未来数十年的农业生产格局将面临重大挑战：既要实现农业产量增长与可持续生产，又需优化水肥投入效率。鉴于当前及未来若干边际与干旱地区均存在水资源短缺问题，且农业生产亟需向更可持续的方向转型，选育适配低投入种植条件的作物品种已成为当务之急。
本研究以42份番茄基因型为材料，在位于意大利与西班牙的两处有机农场（试验环境）中，设置标准栽培（对照组）、无氮施肥及水分胁迫（灌溉量为非胁迫组的30%）三种处理，测定了与植株、果实及根系特性相关的32项形态生理与农艺性状。
所有性状均表现出广泛的变异幅度，且不同处理与栽培地点间均存在显著差异。对基因型（G, Genotypic）、环境（E, Environmental）与处理（T, Treatment）三类因素的解析结果显示，三类主效因素对多数性状均具有极显著影响，其中基因型是多数性状变异的主要来源。基因型-环境互作（G×E）同样具有重要影响，而基因型-处理互作（G×T）与环境-处理互作（E×T）的相关性相对较弱。仅果实重量与脐腐病两项性状在三因素互作（G×E×T）下表现出极显著差异。
在两处试验点中，减少灌溉量均显著提升了果实可溶性固形物含量；而氮素胁迫与水分胁迫则普遍导致果实重量与总产量下降。尽管如此，仍有部分种质在胁迫栽培条件下的表现优于对照组。供试种质中，杂交品种在产量性状上表现优异，而地方品种与传家宝品种整体上则具备更优的品质表现。
这表明，可同时利用古老品种的遗传变异与杂交品种的产量杂种优势，选育出在最优与亚最优栽培条件下均更适配有机农业的新品种。本研究结果为有机农业专用番茄新品种的选育提供了思路，同时也为实现更可持续的番茄栽培提供了水肥管理方面的参考建议。