Five-year-old `Braeburn' apple trees (Malus domestica Borkh.) on MM.106 rootstock were studied to determine plant and fruit quality responses to reduced plant water status late in the season. Trees were irrigated or not irrigated. Those not irrigated developed reduced xylem water potential and stomatal conductance from 110 and 132 days after full bloom (DAFB), respectively. However, they showed no reduction in photosynthetic rates. Fruit were harvested at stage 1 (S1), starting 167 DAFB, or stage 2 (S2), starting 180 DAFB. At S1, fruit had higher soluble solids concentrations, enhanced red skin pigmentation, and a tendency for higher sorbitol concentrations. Total soluble sugar concentrations at final harvest showed no difference between treatments, but fruit from the nonirrigated trees showed earlier sugar accumulation during the season. Such fruit also had reduced Ca+2 concentrations at S1 and S2 relative to those on plants that were irrigated. No incidence of any disorder was found in fruit from either treatment at harvest or after 12 weeks of 0C storage.
T.M. Mills, M.H. Behboudian, P.Y. Tan, and B.E. Clothier
T.K. Hartz, R. Mullen, M. Cahn, and G. Miyao
Trials were conducted in nine commercial processing tomato fields in California from 1994 to 1995 to assess the effects of potassium fertilization on fruit yield and quality. Sites were selected to represent a range of ammonium acetate extractable soil K levels (91 to 284 mg·kg–1, top 30 cm) and K release rates (K at 1.8 to 8.5 mg·kg–1·d–1). Potassium was applied in furrow or drip irrigation during the fruit bulking stage at seasonal rates from 90 to 135 kg·ha–1. Significant yield increase (4% to 24%) was observed at three of the four sites with extractable soil K <125 mg·kg–1 (K released at <3.1 mg·kg–1·d–1); no yield response was observed at the five sites with greater soil K supply. Fruit color and soluble solids content was unaffected by K fertilization at any site. Additionally, red fruit of two cultivars (`Halley' and `Heinz 8892') were collected from 80 commercial fields in 1995 and evaluated for soluble solids content, color (of a comminuted sample as well as visual ranking of internal and external ripening disorders), and tissue K concentration. Fruit K concentration was poorly correlated with any quality characteristic. We conclude that yield response to K fertilization can be adequately predicted by either soil test method and that K supply plays a relatively minor role in tomato fruit quality under representative field conditions.
Maria M. Jenderek and Barbara Hellier
The fruit of several Opuntia species (prickly pear) are a good source of calcium, potassium, and ascorbic acid and are consumed fresh or processed as juices or preserves. Plants of Opuntia may be grown in arid and semiarid environments on marginal soils. Various cultivars, particularly in the species Opuntiaficus-indica, are grown commercially in the United States, Israel, Italy, Mexico, and South Africa. There is a need for new sources of genetic diversity and subsequent germplasm evaluation, and until recently, no publicly maintained germplasm collection of Opuntia existed in the United States. The purpose of this study was to evaluate fruit quality of 25 Opuntia accessions, originating from six countries, and maintained at the USDA collection at the National Arid Land Plant Genetic Resource Unit, Parlier, Calif. The largest fruits were harvested from plants of accessions PARL 201, 202, and 228 (227.6, 247.3, and 231.3 g/fruit, respectively). The hardest peel was on fruits of PARL 225 and 234 (both 3.7 kg), and fruit pulp of the same two accessions had the highest firmness (2.3 and 2.4 kg, respectively). Soluble solids in mature fruit varied from 6.1% (PARL 231) to 15.0% (PARL 254). The fruit color ranged from light yellow through orange, pink to dark purple. These characteristics and other traits such as fruit acidity, presence of spines, and seed mass/fruit indicated that the material represents a diverse germplasm collection, usable for future cultivar development.
Esmaeil Fallahi, Bahar Fallahi, and Michael J. Kiester
and fruit quality in apples which are critical issues in many parts of the world, including the Pacific northwestern region of the North America ( Fallahi et al., 2007a ; Neilsen et al., 1994 , 2009 ). Leib et al. (2006) indicated that fruit size
Esmaeil Fallahi, Denise Neilsen, Gerry H. Neilsen, Bahar Fallahi, and Bahman Shafii
United States. Irrigation methods and injection of nutrients, particularly nitrogen, through water (fertigation) also play major roles in apple fruit quality and production ( Fallahi et al., 2001a ; Neilsen et al., 2009 ). Irrigation with a drip system
Rachel Leisso, Ines Hanrahan, and Jim Mattheis
breakdown, although soluble solids have been documented to be negatively correlated with soft scald incidence ( Tong et al., 2016 ). The goal of this study was to assess readily accessible field temperature data and easily measurable fruit quality
Kristine M. Lang, Ajay Nair, and Kenneth J. Moore
yield ( Waterer, 2003 ), reduce foliar diseases ( Lamont, 2009 ), and improve fruit quality ( O’Connell et al., 2012 ). High tunnel tomato production can greatly increase crop profitability compared with open-field production ( Galinato and Miles, 2013
Juan I. Valiente-Banuet and Alejandro Gutiérrez-Ochoa
above 36 °C caused flower drop, as young leaves presented a greater ability to obtain phloem photoassimilates than did the developing fruitlets ( Aloni et al., 1996 ). Environmental conditions can affect yield and fruit quality attributes of Capsicum
Esmaeil Fallahi, Bahar Fallahi, and Bahman Shafii
dwarfing rootstocks resulted in the earliest ripening. Rootstock can also influence scion leaf and fruit mineral concentrations and, thus, indirectly affect fruit quality and yield ( Fallahi et al., 2001a , 2001b ). Ebel et al. (1993) in a comprehensive
Yun Kong, David Llewellyn, Katherine Schiestel, Martha Gay Scroggins, David Lubitz, Mary Ruth McDonald, Rene Van Acker, Ralph C. Martin, Youbin Zheng, and Evan Elford
). Correlation analysis was used to determine the relationship between marketable fruit yield or fruit quality traits vs. growth of the bitter melon plants. Results Environmental parameters. Weather conditions during the whole 2015 growing season were generally