Search Results (7)

Soybean (Glycine max) is a predominantly self-pollinating crop; however, its flowers exhibit traits associated with insect pollination. While several studies report yield benefits from floral visitation, others suggest little or no effect, and few have assessed pollen limitation through direct hand-pollination experiments. Here, we assess pollinator contribution and pollen limitation through two manipulative common garden experiments using different soybean cultivars. First, we assessed the contribution of pollinators by comparing reproductive variables between caged (pollinator excluded) and open-pollinated plants over two growing seasons. Second, we supplemented flowers with cross-pollen to test for pollen limitation, evaluating pollen-tube growth, pod set, seed number per pod, and seed weight. Pollinator exclusion did not significantly reduce total pod or seed production per plant, but open pollination increased seed set (seeds per flower) by ~16%. In contrast, hand supplementation substantially improved reproductive success at the flower level, tripling pod set probability and increasing seed number per pod by 40%. Additionally, both open-pollinated and hand-pollinated flowers exhibited higher pollen-tube growth relative to autonomous selfing. These findings highlight that even in largely self-compatible crops like soybean, additional pollen input can enhance reproductive success and help bridge the gap between the ecological and agronomic dimensions of pollination. Full article

The Agrobacterium-mediated technique is widely employed for soybean transformation, but the efficiency of this method is still relatively modest, in which multiple factors are involved. Numerous chemical and physiological cues from host plants are needed for A. tumefaciens attraction and subsequent T-DNA integration into the plant genome. Susceptible genotypes may permit this attachment and integration, and the agronomically superior genotypes with susceptibility to A. tumefaciens would play an important role in increasing transformation efficiency. In this study, we aimed to elevate the Agrobacterium-mediated transformation efficiency of soybean by integrating susceptibility alleles from William82 and flavonoids accumulating alleles from LX genotypes in the same soybean line. The crossing was made between LX () and William82 () soybean by hand pollination. Expectedly, the resulting hybrid soybean progenies inherited susceptibility traits and high flavonoid contents (i.e., genistein, genistin, apigenin, naringenin, quercetin, and cinnamic acid) essential for potential plant–pathogen interaction. Furthermore, the progenies and susceptible William82 soybean were subjected to transformation using A. tumefaciens (GV3101) harboring the GmUbi-3XFlag-35S-GFP and reassembled GmUbi3XFlag-35S-GFP: GUS vectors during separate events. Important transformation-related traits like shoot induction and shoot regeneration ability were also significantly improved in progenies. The progenies designated as ZX-3 exhibited superiority over the William82 parental line in all three traits, i.e., shoot induction, regeneration, and Agrobacterium-mediated transformation. The transient transformation efficiency of the ZX-16 line was remarkably higher when half-cotyledon explants were wounded and transformed with A. tumefaciens harboring GUS assembly vector and then co-cultivated on MS medium supplemented with 2 mg/L spermidine, 0.3 g/L GA3, 0.3 mg/L kinetin, and 1.3 mg/L 6-benzylaminopurine. In addition, the shoot elongation was also higher than that of William82 after two weeks of culture on the shoot induction medium. The newly generated soybeans have the potential to serve as a valuable source for high transgene production and represent a promising avenue for future soybean varietal development. Full article

Paraphalaenopsis labukensis Shim, A. Lamb & C.L. Chan (P. labukensis) is an endangered monopodial epiphytic orchid threatened due to habitat fragmentation and overharvesting. Consequently, this research aimed to achieve in vitro propagation of P. labukensis through asymbiotic seed germination and seedling development. This study focused on identification and optimizing capsule maturity, basal media and nutrient requirements. In addition, after hand pollinating the plant, their capsules’ flowers, length, girth, and colour variations were recorded weekly to ascertain morphological maturity characters of this species. Murashige and Skoog (MS), Knudson C (KC), and Vaccin and Went (VW) basal media were used to determine seed vegetation at 60, 90, and 120 days. Subsequently, for the proliferation and development of protocorms, the best basal media were those supplemented with different organic additives (coconut water (CW) and banana homogenate (BH)) and plant growth regulators (PGRs). As a result, 120 days after pollination (DAP) was chosen as the best capsule age for germination since the capsules had reached maturity. The highest germination rate was attained after 90 days of culture in Knudson C (KC) medium, with 98.78 ± 0.89%, followed by Murashige and Skoog (MS) medium, with 92.80 ± 3.26%. The KC supplemented with 0.5 mg/L NAA media documented a maximum percentage of 17.25 ± 0.96%. The 5 g/L (w/v) BH recorded a higher protocorm proliferation percentage than CW. Additionally, after 150 days of culture (DOC), this medium combination produced the most leaves, averaging four or five. The result of this present study has successfully established an effective in vitro propagation protocol for this species. Full article

Pollination is critical for the production of many crops, and both insect- and wind-based pollination systems are increasingly disrupted by bloom asynchrony, weather events, and high demand for available insect pollinators. Artificial pollination systems can provide a security of yield even in poor pollination scenarios, and have been attracting increasing attention over the past decade. Here, we review pollen collection and pollen application technologies that have been employed to date. Major categories of mechanical pollination technology include: hand-pollination, handheld and backpack devices, vehicle-mounted devices, unmanned aerial vehicles (UAVs), and robotic and autonomous pollinators. The majority of the artificial pollination systems above are used to supplement natural pollination, but for some crops, these systems were found to perform adequately by themselves, including kiwifruit, olive, date palm, walnut, tomato, and hybrid maize seed. These systems often treat pollen as a system input, creating a chicken-and-egg problem in which the system is not economical without pollen and the pollen is not economical to collect without wide uptake of the system. To combat this, there has been success in developing mechanical harvesters for some crop plants (particularly almond and maize), but future work is needed for artificial pollination to be a commercial reality for the increasing number of cropping systems that are experiencing pollination deficits. Full article

Pumpkins and winter squash require insect pollination to set fruit, but only three bee species are important pollinators of these crops in the Northeastern US. To determine if natural levels of pollen deposition are sufficient for full fruit production, open pollination was measured by counting pollen grains on stigmas, and open pollination was compared to supplemental hand pollination for fruit set, fruit size, and seed number. A threshold of 2300 pollen grains per stigma was sufficient for full pollination and fruit production. This threshold was met in 79 out of 80 combinations of site and sample date over four years on farms across Connecticut with a wide range of field sizes and pest management practices. Along with stigma collection, bees per flower were counted hourly on 100 flowers along a transect. Counts of bumble bees on female flowers were more closely related to the amount of pollen deposited than counts of bees on all flowers or counts of honey bees or squash bees on female flowers. There was tremendous variation in abundance of the three bee species on female flowers across farms within a year and even among years on a single farm. Full article

The deficiency of pollen grains for ovule fertilization can be the main factor limiting plant reproduction and fitness. Because of the ongoing global changes, such as biodiversity loss and landscape fragmentation, a better knowledge of the prevalence and predictability of pollen limitation is challenging within current ecological research. In our study we used pollen supplementation to evaluate pollen limitation (at the level of seed number and weight) in 22 plant species growing in a wet semi-natural meadow. We investigated the correlation between the pollen limitation index (PL) and floral traits associated with plant reproduction or pollinator foraging behavior. We recorded significant pollen limitation for approximately 41% of species (9 out of 22 surveyed). Seven species had a significant positive response in seed production and two species increased in seed weight after pollen supplementation. Considering traits, PL significantly decreased with the number of pollinator functional groups. The relationship of PL with other examined traits was not supported by our results. The causes of pollen limitation may vary among species with regard to (1) different reproductive strategies and life history, and/or (2) temporary changes in influence of biotic and abiotic factors at a site. Full article

The aim of the apricot-breeding program in the Horticultural Faculty in Lednice, that has been developed since 1981, is to obtain new adaptable cultivars, which combine most of the valuable biological traits. Standard breeding techniques, such as crossing by emasculation and hand pollination, self-pollination and open pollination, were employed. A total of 1.154 crossings were produced from more than 110 different parents. So far more than 20,000 seedlings have been obtained, of which about 13,000 have already been evaluated. The most interesting selections were grafted and planted in trial orchards (we now have more than 650 elite genotypes). Ten of these have already been registered, and further promising new hybrids have been submitted for registration and law right protection (Betinka, Candela, Sophia and Adriana). The basic prerequisite for the initiation of the breeding program was a large collection of genetic resources, established and gradually supplemented since the 1970s. At the present time, we preserve and manage more than 300 accessions of apricot trees. In the frame of the descriptive work of the genetic resources and in order to use in breeding, a collection of apricots has been evaluated. We selected the genotypes and characters relating to an increased level of adaptation to the environment. Full article