sampling protocol. Sampling entire breadfruit leaves is impractical due to their size (we have measured leaves up to 1.4 m in length). Thus, implementing a method that uses a portion of a leaf is necessary. Our primary objective was to assess leaf location
live 12 and 9 months, respectively ( Salazar-GarcÃa et al., 2007b ). This research was undertaken to determine or validate the leaf sampling period currently used for ‘Hass’ avocado in Nayarit and had the following objectives: 1) to establish the
an alkaline soil and attributed variability in nutrient accumulation, nut quality, and yield to genetic differences in both seed-propagated rootstock and scion cultivar. Tree-to-tree nutrient variability has implications for leaf sampling
Abstract
This report, describes a rapid and convenient method to obtain leaf disc samples for electron microscopy. It was developed in connection with bio-chemical-ultrastructural studies of herbicidal effects on protein synthesis. It was important to speed up the sampling time and to obtain uniformly sized samples.
Concentrations of nutrient elements in randomly selected soil samples taken at a 3-inch depth or the depth of the surface organic pad correlated poorly (R2= < 0.34) with leaf nutrient concentrations randomly selected from the same fields. Average leaf N concentrations in 74 of 79 fields sampled were above the 1.6% standard, while leaf P was below the 0.125% standard in 62 of the 79 fields. Leaf K, Ca, and Mg concentrations were above the standards 0.400%, 0.270%, and 0.130%, respectively in all fields. The average depth of the organic pad was 2.23 cm, ranging from 0 to 10.16 cm. Seventy five percent of the fields had organic pads 0.127-2.54 cm thick and 20% greater than 2.54 cm.
In an attempt to improve correlations, leaves within a 0.01M2 quadrat were sampled from 110 clones in 10 commercial blueberry fields and leaf nutrient concentrations compared with nutrient concentrations in 3-inch soil samples taken directly beneath the quadrat. The strongest correlation was between soil Mn and leaf Mn (r2= o.59). Leaf samples, although more expensive than soil samples, appear to be a better indicator of lowbush blueberry fertilizer requirements than soil samples.
Abstract
Four types of leaf samples were taken in June and August 1966 from 11 early, mid-season, and late cultivars of highbush blueberry Vaccinium corymbosum L. The first three were the 1st, 2nd and 3rd mature leaves of current-season shoots subtending fruit clusters and the 4th was a composite collection of these leaves. Each sample was analysed for N, P, K, Ca, Mg, and Fe.
Differences among cultivars were significant for all elements tested. Every cultivar had less Ca in June than in August, and most cultivars had lower Mg in June than in August. Most cultivars had similar N and Fe content in both months, but had higher P and K in June than in August. In June, K was lower in samples of young leaves than in composite samples. In August, young leaves were higher in Mg. In June, composite samples were higher in P than the second and third mature leaves. Cultivars, as well as sampling position and time will be important in evolving diagnostic criteria in highbush blueberry leaf analysis.
NIR-based tissue analysis has proven useful in Australia for making fertilizer recommendations for rice and wheat growers. Viticulturists have for some time made fertilizer recommendations based on tissue analysis, although there is some debate in the literature as to whether younger or older leaves or petioles provide the best indicator of vine nutrient status for diagnostic purposes. The aim of our research has been to develop NIR-based nutrient analysis for grape producers. Aspects of sample collection, including leaf lamina vs. leaf petiole; leaf opposite the basal cluster vs. youngest leaf; aspects of drying (microwave vs. convection oven), have been reexamined from the viewpoint of convenience, cost, accuracy, and turnaround time with respect to NIR analysis. We have refined procedures for collecting and microwave-drying samples. The samples of leaves and petioles were collected from vines in most wine-growing regions of Australia and included all the major wine grape and some dried fruit cultivars on their own and, in some cases, on rootstocks. At this stage, we have developed preliminary NIR calibrations for the major nutrient elements in both leaf lamina and petioles.
Broccoli (Brassica oleracea L. Italica group) breeders routinely use anther or microspore culture to produce dihaploid (diploid), homozygous lines. During the culture process, polyploidization occurs and diploid regenerants can result. However, polyploidization may not occur at all, or it may involve a tripling or quadrupling of the chromosome complement. Thus, regenerated populations must be screened to identify the diploids that are the regenerants most likely to set seed and serve as inbred lines. DNA flow cytometry has proven a useful procedure for determining ploidy of anther derived regenerants. This study was undertaken to evaluate the effect of leaf age and sampling procedures on ploidy determination via flow cytometry. Anther-derived plants were analyzed at a four- to five-leaf stage (transplant stage) and at time of heading (mature plant stage). In addition, leaves were sampled on a given date and stability of the flow cytometry preparations was evaluated over 7 days. Lastly, the stability of ploidy readings of leaves stored at 4°C was examined over a 7-day period. In only one case out of 123 comparative assays did leaf age affect ploidy determination. For that exception, a haploid at transplant stage was a diploid at the mature plant stage. Flow cytometry preparations and also leaves stored at 4°C gave consistent ploidy determinations up to four days after preparations were made or tissue was refrigerated, respectively. These results indicate that broccoli breeders can make flow cytometry preparations on site and send them offsite for flow cytometry analysis. Alternatively, leaves could be refrigerated, sent offsite, and then prepared and analyzed at another location.
Abstract
Leaf B, Ca, S, and Mo levels differed markedly in 14 red raspberry genotypes, and significant differences of lesser magnitude occurred for N, P, K, Mg, Na, Zn, Fe, Sr, and Cd. Levels of Mn, Al, and Cu were not significantly affected by genotypes. All elemental concn, except those of Mg and Mo, were influenced significantly by sampling date in ‘Willamette’. Age of plant had little effect on leaf chemical composition.
Abstract
Nutrient concentration of azalea (Rhododendron sp.), juniper (Juniperus sp.), crapemyrtle (Lagerstroemia indica L.), and camellia (Camellia sp.) did not differ between leaves dried in microwave or conventional ovens.