Browse results
Summary
Resin canals produce and transport oleoresins that are important for tree defenses within the Pinaceae family. Rapid measurement techniques are needed to better understand how resin canal characteristics vary due to genetic and environmental effects. Here we describe a semi-automated microscopy imaging system that was built for quantifying longitudinal resin canals. Tree increment cores from 210 loblolly pine (Pinus taeda L.) trees were prepared into radial strips and the transverse surface of the samples polished with 400 and then 600 grit sandpaper. Each sample was imaged along its entire length (pith to bark) with the images collected from a monochrome camera connected to a Plan Fluorite 4× objective lens. The samples were imaged on the transverse surface via transmitted 850 nm near-infrared light directed at the radial surfaces of the samples. A total of 24 153 images were collected and then processed offline in Python using the Open Computer Vision Library (OpenCV) using a series of algorithms including contrast correction, noise removal, thresholding, contour identification, erosion, and dilation. A total of 24 491 resin canals were identified and their size quantified. The resin canals were assigned into annual rings and positioned within the earlywood or latewood of a ring using cross-correlation whereby a pseudo-density value was derived from the images and matched with density values measured by X-ray densitometry. Of the total resin canals identified, 51.5% were in the earlywood and 48.5% in the latewood, with the majority being detected in the earlywood in the first six years and the latewood in years 7 and above. This study represents the most information collected on the resin canals of loblolly pine. The detailed description of the hardware and image analysis methods should serve as a useful guide to others interested in imaging resin canals as well as other anatomical features.
Abstract
The study aims to determine the optimal regimes of mineral fertilization for the yield of commercial watermelon fruits. The research goal is to analyze how fertilization regimes affect the growth parameters of this plant, such as weight per fruit and average fruit weight per plant. The research subjects are watermelon varieties, such as two Crimson Sweet varieties (including hybrid Producer Hollar) and Kholodok. The study involved a field survey on the territory of Zhana Tau, a farm located in the Aktobe area of the Republic of Kazakhstan. The experimental design encompassed the following fertilizer applications: Variant I – N30P40K60, Variant II – N60P60K120 and Variant III – N90P60K120. The study found that mineral fertilizers have a significant impact on the yield and growth parameters of watermelon fruits. After the application of N30P40K60, the weight per fruit was 8.13 kg for Crimson Sweet and 8.35 kg for Kholodok. The highest fruit weight indicator, 11.45 kg, was achieved when hybrid Producer Hollar was cultivated with N90P60K120. The highest yield (55.9 t/ha) was recorded when growing hybrid Producer Hollar with N90P60K120. The yield of the Crimson Sweet and Kholodok varieties, with the same level of fertilization, amounted to 49.6 t/ha and 51.2 t/ha, respectively. Correlation-regression analysis of the data on watermelon yield showed that this parameter tends to increase with the increase in the use of mineral fertilizers. Therefore, further research may focus on studying the influence of even higher levels of each macroelement and their combined effects on crop structure and fruit quality in watermelon cultivation.
Abstract
This is the first initiative study to provide quantified levels of four endogenous phytohormones during the induction, regeneration, maturation and germination stages of somatic embryogenesis (SE) in banana, using immature male bud explants, in the popular commercial triploid cultivar Grand Naine (AAA). Phytohormones are known to play a major role in the regulation of SE and most protocols have been developed for various cultivars of banana following empirical approaches. Although, several reports are available with regard to the impact of growth regulators exogenously supplemented to the media, the vital role of endogenous growth hormones in various developmental stages of SE remain unclear in banana. Reverse Phase High Performance Liquid Chromatography (RP-HPLC) was used to analyze endogenous status of indole acetic acid (IAA), zeatin, gibberellic acid (GA) and abscisic acid (ABA). Results from this study revealed that endogenous IAA and GA along with exogenous auxin play a major role in the induction of embryogenic competence of male bud explants. The levels of endogenous IAA and zeatin were found to be higher in embryogenic calli than non-embryogenic calli, although three different types of exogenous auxins were supplemented in callogenesis medium, but not cytokinin. Higher level of ABA and GA was observed in early and late developmental stages of somatic embryo, respectively. GA also played a predominant role in germination of somatic embryos. These findings will be applied for improvement of SE protocol in recalcitrant banana cultivars by suitably altering or supplementing exogenous growth hormones.
Abstract
Summer pruning is an important horticultural operation that is performed to manipulate tree response so as to make it better manageable without a reduction in yield and fruit quality. But the timing is also an important factor in performing this event. Keeping in view the above facts, the present investigation was carried out to elucidate the ‘differential response of summer pruning timing on cropping behavior in low-chill peach cvs. Florida Prince and Shan-i-Punjab’. The experiment was carried out at the experimental orchard of the Department of Fruit Science, College of Horticulture and Forestry, Neri, Hamirpur (HP) during the years 2018–2019 and 2019–2020. There are six treatments in the experiment, each with four replications. T1: no pruning; T2: 25% summer pruning on July 10th + winter pruning (WP); T3: 25% summer pruning on July 20th +WP; T4: 25% summer pruning on July 30th +WP; T5: 25% summer pruning on August 10th +WP); and T6: standard winter pruning (SWP). According to the study’s findings, combining 25% summer pruning on July 10th with winter pruning resulted in the greatest improvement in terms of vegetative, flowering or blooming, and qualitative parameters, namely fruit weight, fruit shape index, total soluble solid, and sugar content. However, Florida Prince showed positive enhancement of various characteristics and performed better than Shan-i-Punjab.
Abstract
Zinc (Zn) deficiency is a widespread problem in agricultural soils all over the globe. As an essential element, Zn plays a decisive role in realization of high yields of wheat, the changes in activities of Zn dependent enzymes and its accumulation in various plant parts of wheat varieties of differential susceptibility. The aim of the study was to examine the activities of Zn dependent enzymes, i.e. superoxide dismutase (SOD), carbonic anhydrase (CA); chlorophyll and grain protein content and to evaluate the pattern of Zn transport in two wheat varieties (UP2628-Zn efficient and UP262-Zn inefficient). All these parameters were evaluated in a pot experiment under different modes of Zn applications viz., control (C), soil application (S), foliar application (F), soil+foliar application (S+F). The accumulation of Zn in different plant parts of both wheat varieties under different Zn supply regimes was monitored in a separate autoradiography experiment where radiolabelled Zn was used. An increased activity of SOD, CA and total chlorophyll content in leaves, high protein content in grains and 65Zn accumulation was observed under S+F mode of Zn application. Zinc efficient variety (UP2628) showed higher SOD, CA activities, chlorophyll content in leaves and grain protein content as compared to UP262. Both soil application + foliar spray of Zn and cultivation of Zn efficient variety (UP2628) can be best approach for Zn biofortification of wheat.
Summary
Fossil woods are preserved as calcareous permineralizations in the Upper Cretaceous Northumberland Formation on Collishaw Point, Hornby Island, British Columbia, Canada. They are well preserved, often including peripheral tissues, and reveal the diversity and structure of vegetation in the region ca. 72 million years ago. We describe a new genus and species based on two specimens. Two specimens were cut using a rock saw to expose the fossil wood in transverse and longitudinal sections. Thin sections were prepared using the cellulose acetate peel technique. Peels were mounted on slides with Eukitt mounting medium. Anatomical description follows the IAWA guidelines. We compared the anatomy of the fossils with that of other plants using data available in the published literature and the InsideWood database. The combination of wide vessels and high vessel frequency given the narrow diameter of the stem, combined with the abrupt increase in vessel diameter near the pith indicates this plant had hydraulic properties typical of a climbing plant (liana). The anatomy of the rays, the arrangement of the vessels and their pitting, and the thickness of the bark are also consistent with the climbing habit, but not diagnostic of any extant family. This is the second species of liana to be described from the Hornby Island assemblage, providing new information about the composition of structurally complex mixed conifer–angiosperm forests in the Late Cretaceous of western North America.
Abstract
Peanut is not only an important economic crop but also considered to be as a kind of functional food. However, the presence of calycosin, a bioactive isoflavonoid, in peanuts is still unknown. In this study, calycosin was firstly identified in leaves, needles and pods of four peanut cultivars examined including Yuanza 9102 (P1), Kainong 176 (P2), Zhuhua 2 (P3) and Yuhua 23 (P4). Moreover, the effects of three nitrogen fertilization levels (N0: 0 kg/ha, N1: 75 kg/ha, N2: 150 kg/ha) on calycosin accumulation in leaves, needles and pods of four different peanut cultivars at DAF30, DAF60 and DAF90 were investigated. The results showed that calycosin content varied from 0.87 to 718.83
Abstract
Submergence negatively affects the plant growth and yield of rice genotypes, which in turn results in huge financial loss. Thus, identification of submergence tolerance rice genotypes is needed for sustainable rice cultivation in flood-prone areas. Keeping this in view, a two-year (2019 and 2020) field study was undertaken at Rice Research Farm of Bihar Agricultural College, Bihar Agricultural University, Sabour, Bhagalpur to investigate and compare the yield responses of rice genotypes under submergence and normal growing conditions. Twenty-five days old seedlings of 25 rice genotypes were transplanted in a randomized complete block design in two replicates, which were allowed to grow under normal practice for the next 25 days. Thereafter, the 50-day old plants were completely submerged with turbid water of 1.5 m height for the next 18 days. After de-submergence, all the recommended agronomic practices were adopted during the rest of the crop period. Under submergence, higher grain yield was recorded under all the genotypes during 2020 as compared to 2019 mainly due to higher temperature and lesser rainfall during 2020. Under submergence conditions, Jalmagna, Nona Bokra and Swarna Sub 1 were the best performers having produced average yields of 3,167, 2,786 and 2,741 kg/ha, respectively. Whereas under normal growing practice, Swarna Sub 1, Jalmagna and Sudha were the first three best performing genotypes producing average yields of 5,063, 4,565 and 4,456 kg/ha, respectively. Therefore, Jalmagna should be preferred for cultivation in the flood-prone regions of the state, however in non-flooded areas; Swarna Sub 1 may be cultivated.
Abstract
During the cropping season 2016-2017, an experiment was conducted in a split plot design to study the response of 25 wheat genotypes to drought stress under irrigated and minimal irrigation conditions. Different drought tolerance indices for 25 bread wheat (Triticum aestivum L.) genotypes were evaluated. The calculation drought tolerance indices was based on the grain yield of wheat under irrigated and water stress conditions. The result indicated a significant effect of drought stress on the yield of different wheat genotypes based on mean values of different drought tolerance indices. Among the studied different indices, mean productivity (MP), stress tolerance index (STI), and geometric mean productivity (GMP) were more efficient to discriminate between drought sensitive and drought tolerant genotypes based on the calculation of correlation coefficient and multivariate analysis. Twenty-five genotypes were classified into tolerant and susceptible groups through drought tolerance indices using cluster analysis. Among the genotypes, C-306, WH 1236, WH 1235, and GW 477 having higher yields under drought conditions which showing their stability under stress conditions. The most yield stable genotypes under adverse environment were identified by multivariate analysis of drought tolerance indices individually or in combination. From the result, we concluded that GMP, MP and STI are more efficient drought tolerance indices among other indices to identify stable genotypes under stress conditions.