关键词: 大青葡萄, 露地大棚架栽培, 空间位置, 果实品质, GC-IMS技术, 挥发性物质

Abstract:

In order to realize the quality directional control and establish the quality evaluation system of open-field cultivation with big-trellis for‘Daqing grape’ （Vitis vinifera L. Daqing）， at fruit mature stage， the related components of chemical， texture indicators and volatile organic compounds of ‘Daqing grape’ fruits at different spatial positions on the big-trellis and per grape-cluster were determined by texture profile （TPA） analysis and gas chromatography-ion mobility spectrometry （GC-IMS） technology. The results showed that compared with‘the middle fruit of big-trellis’（TMF） and‘the anterior fruit of big-trellis’（TAF）， the contents of total sugar （Ts） and vitamin c （Vc） in‘the posterior fruit of big-trellis’（TPF） fruit significantly （P<0.05） increased by 8.92% and 10.38%， 22.29% and 62%， respectively， but total acid （Ta），TAF fruit had the highest content， which increased by 11.81% and 17.21%， respectively， compared with TMF and TPF； the contents of soluble solids （Tss）， Ts and Vc of ‘the shoulder fruit of single ear grapes’（TSF） were significantly （P<0.05） higher than those of the tip fruit of single ear grapes（TTF）， and increased by 5.62 %， 6.10 % and 13.02 %， respectively. The Ta content of TTF was the highest， which was 9.46% higher than that of TSF. The analysis of physical indicators showed that the single grain weight and hardness of TPF fruit were higher than those of TMF and TAF， and increased by 14.84 % and 19.12 %， 4.44 % and 5.36 %， with significant differences （P<0.05）； the fruit single grain weight and hardness of TSF were higher than those of TTF， and with increasing of 6.02 % and 3.22 %. The visualization analysis of volatile organic compounds for fruit by GC-IMS technology showed that TAF fruits possessed the aroma characteristics of grass and malt. TMF showed a kind of fat aroma； and the fruit （pineapple， citrus）， green grass aroma characteristics were shown at TPF； concomitantly， the peak volume of esters and terpenoids in TPF fruit was significantly （P<0.05） higher than those in TMF and TAF， such as ethyl acetate， ethyl propionate， α-terpinene， etc.， with increasing of 602.00%， 98.10%， 372.13% and 5 897.80%， 744.00%， 1 969.28% ； and the aromas of green grass and cream （E-2-hexenal， 3-hydroxy-2-butanone） were prominent in TTF， while the aroma of fruit and nut （n-pentyl butanoate， acetoxyacetone， guaiacol） were obvious in TSF； the accumulation of some esters and terpenoids （ β-pinene， α-phellandrene， ethyl acetate， etc. ） in the TSF fruit were significantly （P<0.05） higher than that in the TTF， with the increasing of 27.68%， 50.88%， and 785.43%.This paper combined the chemical indicators， with physical indicators and volatile organic compounds characteristics， the quality orders of ‘Daqing grape’ fruits at different spatial positions on the big-trellis were TPF>TMF>TAF， and TSF>TTF at different spatial positions of per grape-cluster. It was found that there were differences in fruit quality and volatile organic compounds at different spatial positions on the big-trellis in open field cultivation of ‘Daqing grape’， and it also showed that quality differences of per grape-cluster fruit at different spatial positions. Above results indicated that the importance of directional regulation of pre-harvest quality and establishment quality evaluation system for‘Daqing grape’ fruit， to guide post-harvest fresh-keeping and supply of different target markets.

Key words: Daqing grape （Vitis vinifera L.， Daqing）, open field cultivation of big-trellis, spatial position, fruit quality, GC-IMS technology, volatile organic compounds