bulking period. The plants enter dormancy in the fall and are overwintered in a minimally heated or unheated low or high tunnel during the first dormancy period. The following spring, vining stems emerge from above and/or below ground tissue and are
Uttara C. Samarakoon and James E. Faust
Dario J. Chavez and José X. Chaparro
markers associated with traits of interest, permitting the use of marker-assisted selection (MAS) for traits expressed in late development ( Gulsen et al., 2010 ). Bulked segregant analysis (BSA) is a rapid procedure used to efficiently identify markers
Arthur Villordon, Don LaBonte, and Julio Solis
as the “initial tuberous-root bulking stage” wherein the ratio of initiated SRs and lignified ARs determined eventual SR yield. During this stage, ARs undergo secondary or anomalous cambium growth that signals successful transition into SRs. During
Diego Cunha Zied, Marli Teixeira Almeida Minhoni, J. Emilio Pardo-González, and Arturo Pardo-Giménez
vital for the success of the CACing technique ( Tschierpe, 1999 ). In Spain, the use of Phase III composting technology in bulk has been recently introduced. This technology provides final composts with relatively low moisture contents (± 61%). To
Min Wang, Wenrui Liu, Biao Jiang, Qingwu Peng, Xiaoming He, Zhaojun Liang, and Yu’e Lin
frequencies of parental alleles in the population of bulked individuals. The SNP index was calculated at all SNP positions by in-house Perl scrips with the following values: SNP index >3 and SNP depth >6. A slide window analysis was applied to SNP index plots
Wayne C. Porter and Richard L. Parish
The initial investment of a precision seeder is cost prohibitive to many small vegetable growers. This study was initiated to evaluate the use of a relatively inexpensive bulk seeder to plant cabbage (Brassica oleracea L. Capitata). Cabbage was direct-seeded with a precision seeder or a relatively inexpensive bulk seeder. Treatments with the bulk seeder consisted of blending viable hybrid seed with nonviable, nonhybrid seed at several ratios to reduce hybrid seed cost and optimize plant spacing. Seed ratios represented 10, 20, 30, 40, 50, and 100% viable seed. Pre-thin plant stands of 30 and 40% hybrid seed treatments were similar to precision-seeded plant stands. Average head size was greatest with 10, 20, and 30% hybrid seed ratios. Marketable yields were similar for all hybrid seed ratios except the 10% ratio. Production costs per acre for the precision seeder were between that of the 40 and 50% ratios. Net income for 40% hybrid seed was similar to that of the precision seeder.
Luwbia Aranda, Timothy G. Porch, Mark J. Bassett, Laura Lara, and Perry B. Cregan
. Circumlineatus phenotype with precipitation line indicated by the arrow in representative lines from the t z cl G b v virgarcus BC 3 5-593 × t z sel Cl G b v sellatus BC 3 5-593 population of common bean. AFLP and bulk segregant analysis. DNA was
Wayne C. Porter and Richard L. Parish
Cabbage (Brassica oleracea L. Capitata) was direct-seeded with a precision seeder or with a bulk seeder. Treatments with the bulk seeder consisted of blending viable, hybrid cabbage seed with nonviable, open-pollinated seed at several ratios to reduce the cost of planting hybrid seed. The study demonstrated that farmers with small acreages can obtain equivalent net income per acre using bulk seeders compared to using more expensive precision seeders. The study also showed that the additional cost per acre of a precision seeder is small compared to other input costs (for the acreage assumptions used here). Low percentages of hybrid seed in the bulk seeder (10% to 50%) were not economical. Precision seeding to a stand reduced the need for thinning labor and resulted in equivalent yields and net income.
Patricia M. Sweeney and T. Karl Danneberger
The usefulness of random amplified polymorphic DNA (RAPD) in characterizing two perennial ryegrass (Lolium perenne L.) synthetic cultivars, `Accolade' and `Caravelle', was tested. Two out of 10 arbitrary primers produced three RAPD markers that distinguished bulk samples of 30 seedlings. Additional fragments were apparent when DNA from individual seedlings was amplified. Amplification products from bulk samples were not simply the sum of amplification products of individual seedlings and did not reflect all the diversity within or between the cultivars. The study illustrates the need to screen individuals to accurately evaluate the genotypic composition of a synthetic cultivar or heterogeneous population.
Shufu Dong and Huairui Shu
Malus hupehensis Reld apple rootstock seedlings and the rhizobox technique were used in this study. The seeds were collected from healthy mature trees at the Wanshougong Forest Farm in Shandong, China, stratified at 0 to 2 °C for 60 days, sown into growing medium with 1/3 loam soil+1/3 silt sand+1/3 compost manure, grown until the three-leaf stage, and then transplanted into rhizoboxes with four plants in each box. The rhizoboxes were inserted into the ground with the top of the boxes levelled with the soil surface. After the root mattress formed in the center of the box, plants were harvested by carefully dividing each box into rhizoplane, rhizosphere, and bulk soil, and mineral nutrients in each part were analyzed. The relationships were tested between the rhizoplane, rhizosphere, and bulk soil for each nutrent. Significant correlations were found for NH + 4, NO – 3, K, Mg, Zn, and Cu in the rhizoplane, rhizosphere, and bulk soil. There were significant relationships for P and Ca between the rhizoplane and rhizophere, but not between the rhizoplane or rhizosphere and bulk soil. Fe in the rhizoplane closely related to Fe in the rhizosphere but not to Fe in bulk soil. No correlation was found between the rhizoplane and either rhizosphere or bulk soil, but close correlation existed between rhizosphere and bulk soil for Mn.