1. College of Horticulture, Northwest A&F University , Yangling, Shaanxi 712100 , P.R. China
2. Key Laboratory of Protected Horticultural Engineering in Northwest, Ministry of Agriculture and Rural Affairs , Yangling, Shaanxi 712100 , P.R. China
3. Shaanxi Protected Agriculture Engineering Technology Research Centre , Yangling, Shaanxi 712100 , P.R. China
4. Department of Horticulture, The University of Haripur , Haripur 22620 , Pakistan
5. College of Horticulture, Shenyang Agricultural University , Shenyang, Liaoning 110866 , P.R. China