You are looking at 51 - 60 of 28,472 items for

  • User-accessible content x
Clear All
Open access

Rie Sadohara, James D. Kelly and Karen A. Cichy

Common beans are recognized as a nutrient-dense food source that delivers numerous health benefits, but one of the barriers to increasing bean consumption is the limited number of common bean food products. Bean paste, made from bean seed and sugar, has the potential to diversify and expand the way beans are consumed. In this study, commercial white seeded otebo, navy, great northern, and white kidney bean cultivars and one colored cranberry bean were grown in two environments in Michigan and evaluated for bean paste qualities. Characteristics such as paste yield, color, flavor, and stickiness were evaluated on the bean paste. The genotype × environment effect was significant for many of the paste-making qualities and the color values of the unsweetened paste. ‘Snowdon’, the white kidney bean, had superior paste yield of unsweetened paste and whiteness of sweetened paste in both environments. All the white bean cultivars were comparable to Hime, the control otebo cultivar, in terms of low flavor intensity. ‘Powderhorn’, the great northern bean, had high stickiness of sweetened paste, which is preferable. The cranberry bean resulted in dark-colored paste with high flavor intensity. Seedcoat percentage and the ratio of L* and C* obtained via image analysis could be used as indicators for paste yield and whiteness score of the unsweetened paste, respectively. Overall, these results suggest that specific domestically grown white bean cultivars have potential for development as bean paste products, which would add a novelty to the processed dry bean applications in the United States.

Open access

Tao Dong, Fang-cheng Bi, Yong-hong Huang, Wei-di He, Gui-ming Deng, Hui-jun Gao, Ou Sheng, Chun-yu Li, Qiao-song Yang, Gan-jun Yi and Chun-hua Hu

An efficient biolistic transformation system of banana combined with a liquid medium selection system was developed during this study. An embryogenic cell suspension (ECS) of Musa acuminata cv. Baxi (AAA) was bombarded with a particle delivery system. After 7 days of restoring culture in liquid M2 medium, embryogenic cells were transferred to a liquid selection M2 medium supplemented with 10 μg/mL hygromycin for resistance screening. The untransformed cell clusters were inhibited or killed, and a small number of transformants proliferated in the liquid selection medium. After the 0th, first, second, and third generation of antibiotic screening, there were 0, 65, 212, and 320, respectively, vitality-resistant buds obtained from a 0.5-mL packed cell volume (PCV) of embryogenic cell suspension. The β-glucuronidase (GUS) staining, polymerase chain reaction (PCR) analysis, and Southern blot hybridization results all demonstrated a 100% positive rate of regenerated resistant seedlings. Interestingly, the number of buds obtained through third-generation screening was almost equal to that obtained from the original ECS in M2 medium without antibiotics. These results suggested that the liquid medium selection system facilitated the proliferation of a positive transgenic ECS, which significantly improved the regeneration rate of transformants. This protocol is suitable for the genetic transformation of all banana genotypes and is highly advantageous to varieties with low callusing potential.

Open access

Patrick H. Kingston, Carolyn F. Scagel, David R. Bryla and Bernadine C. Strik

Peat and coir are commonly used for substrate production of highbush blueberry (Vaccinium sp.). Perlite is also typically added to improve drainage and stability of the media. The purpose of the present study was to determine how various combinations of each affect growth and nutrition in highbush blueberry. Two cultivars, ‘Liberty’ northern highbush blueberry (V. corymbosum L.) and ‘Jewel’ southern highbush blueberry (interspecific hybrid of V. corymbosum L. and V. darrowii Camp.), were grown for 3 months in media containing 0%, 10%, 20%, or 30% perlite, by volume, and a 1:0, 2:1, 1:2, or 0:1 ratio of peat and coir. At 95 days after transplanting, total dry weight of the ‘Liberty’ plants was greatest in pure peat and progressively less as more coir or perlite was added to the media. Total dry weight of ‘Jewel’ also declined with increasing amounts of perlite but, in this case, was unaffected by the ratio of peat and coir. The response of the plants to perlite did not appear to be a function of pH or nutrition and was most likely related to the effects of perlite on media water relations. Response to peat and coir, on the other hand, may have been due to nutrition and salinity of the media. In both cultivars, a higher amount of peat in the media improved uptake of N, P, Mg, and S and decreased uptake of K, B, Zn, and Na. Coir, on the other hand, contained higher concentrations of Na and Cl than peat. These findings suggest that the use of high amounts of perlite in the media could be detrimental when growing highbush blueberry in substrate, and some cultivars may grow better in peat than in coir.

Open access

Ute Albrecht, Shahrzad Bodaghi, Bo Meyering and Kim D. Bowman

The rootstock plays a large role in modern citrus production because of its influence on tolerance to adverse abiotic and biotic soil-borne stresses, and on the general horticultural characteristics of the grafted scion. In recent years, rootstock has received increased attention as a management strategy to alleviate the devastating effects of the bacterial disease huanglongbing (HLB), also known as “citrus greening.” In commercial citrus nursery production, rootstocks are typically propagated by seed. Because of the increased demand for HLB-tolerant rootstocks, seed supply is often inadequate for the most popular cultivars. Cuttings and tissue culture (TC) propagation are alternative methods to supply adequate quantities of genetically identical rootstocks to be used as liners for grafting. However, there are concerns among nursery owners and citrus growers regarding the possible inferiority of rootstocks that are not propagated by seed. This study investigates the influence of rootstock propagation method on traits of sweet orange trees grafted on four commercially important rootstock cultivars during the nursery stage and during the first year of growth in a commercial citrus orchard. Several of the measured traits during the nursery stage, including rootstock sprouting, grafted tree growth, and root mass distribution were significantly influenced by the rootstock propagation method, but traits were also influenced by the rootstock cultivar. Our results also suggest that for tissue culture-propagated plants, differences in the starting material and the culturing method can affect the grafted tree behavior. Except for canopy spread and scion to rootstock trunk diameter ratio, tree growth during the orchard stage was determined by the combination of propagation method and rootstock, rather than by propagation method alone.

Open access

Lie Li, Yu-xin Tong, Jun-ling Lu, Yang-mei Li and Qi-chang Yang

Light, as the energy and signal sources for plant growth and development, is one of the most important environment factors in recently developed plant factories with artificial light (PFALs). To find the optimal combination of light wavelengths for lettuce (Lactuca sativa cv. ‘Tiberius’) plant growth in a PFAL, four treatments, each using red (R; 662 nm) and blue light (B; 447 nm) with a ratio of 4:1 and photon flux density (PFD) of 150 μmol·m−2·s−1, and mixing, respectively, with 50 μmol·m−2·s−1 of green light (G; 525 nm; RBG), yellow light (Y; 592 nm; RBY), orange light (O; 605 nm; RBO) and far-red light (FR; 742 nm; RBFR), were set up during this experiment. A combination of R and B with a ratio of 4:1 and PFD of 200 μmol·m−2·s−1 was set as the control (RB). The responses of lettuce growth, morphology, anatomical structure of the lettuce leaf, photosynthetic performance, lettuce nutritional quality, and energy use efficiency were investigated. The results showed that RBG, RBO, and RBFR increased the shoot fresh weight of lettuce by 20.5%, 19.6%, and 40.4%, and they increased the shoot dry weight of lettuce by 24.2%, 13.4%, and 45.2%, respectively, compared with those under RB. The Pn under RBY was significantly lower than that under RB, although no significant differences in chlorophyll or carotenoid content were found between RBY and RB. RBG increased the lettuce leaf area, the thickness of the leaf palisade tissue, Pn, and light use efficiency compared with those under RB. Plants grown under RBO showed better photosynthetic capacity, such as higher Pn, ΦPSII, and other photosynthetic parameters. RBFR caused an increase in lettuce leaf area and energy use efficiency, but a decrease in leaf thickness and Pn of the single leaf. Moreover, tipburn injury was observed under RBFR. Therefore, these results demonstrate that RBG and RBO can be considered optimal combinations of light wavelengths for lettuce growth in a PFAL in this experiment, although plant growth can also be improved by using RBFR.

Open access

Andrés Javier Peña Quiñones, Melba Ruth Salazar Gutierrez and Gerrit Hoogenboom

A common problem for decision makers in selecting frost control options is uncertainty about the level of injury that can be caused by low temperatures. During the past few years, the concept of lethal temperature (LT) at which 10% of the bud population dies (LT10) has been used as an index for evaluating the vulnerability of flower buds to low temperature conditions. This concept has shown to be a useful tool for frost control decision-making. However, the current methods used to obtain LT values assume no spatial or temporal variability, which results in a high level of uncertainty. The goal of this study was to develop an approach that decreases the uncertainty based on the known effects of temperature on bud vulnerability. A growth chamber experiment was conducted to determine flower bud vulnerability to low temperature as a function of temperature. The results from this study showed that thermal time expressed in degree days could explain changes in floral bud development and vulnerability to frost injury. According to our findings, LT10 is a fully acceptable index for determining flower bud vulnerability to low temperatures in orchard crops. Based on this information, we found that among the five apple and cherry cultivars analyzed, ‘Gala’ is the least vulnerable to low temperature because it starts at the beginning of spring with a high level of hardiness and increases its vulnerability at a low rate. The approach described in this article may enhance decision-making certainty associated with the timing and methods to increase air temperature in orchards during low-temperature events to avoid frost damage.

Open access

Archana Khadgi and Courtney A. Weber

Caneberry crops (raspberry and blackberry) are globally commercialized specialty crops with a high fresh market value. Field management of canes and harvesting of fruits can be complicated by the presence of prickles (the botanically accurate term rather than spines or thorns) on the stems, petioles, and underside of the leaves. Both field management and fruit harvesting could be simplified by the development of cultivars with prickle-free canes. Scanning electron microscopy (SEM) was used to analyze and compare prickle development in different Rubus species. Comparisons were made between prickled vs. prickle-free red raspberry (Rubus idaeus L.), black raspberry (Rubus occidentalis L.), blackberry (Rubus hybrid), complex hybrid with purple fruit (R. occidentalis × R. idaeus), and the hairy and prickled wineberry (Rubus phoenicolasius Maxim). Samples from stems and leaves with petioles attached were used for imaging. There were distinct differences between prickled vs. prickle-free phenotypes in each species. The images of prickle development suggest that prickles either develop directly from glandular trichomes (in red raspberry and wineberry) or that the signal originates from glandular trichomes (in blackberry). Black raspberry prickle development was similar to that of blackberry, suggesting that prickles developed after a developmental signal from glandular trichomes rather than as a direct development from glandular trichomes. The prickle development in the purple hybrid was unique in the presence of one-sided lumps in the trichomes, which has not been seen in any other Rubus species to date; however, both prickled and prickle-free plants exhibited simple nonglandular trichomes. Unlike previous studies, an increase in the number of simple trichomes was not specific to prickle-free plants, but rather variability among the different genotypes was observed. This study adds to the basic understanding of prickle development in the genus Rubus as a first step in the development of prickle-free versions of important cultivars through gene-editing procedures for improving the ease of field management and harvesting.

Open access

Paul W. Bosland and Danise Coon