Total Shoot Fresh Weight Research Articles

Water use efficiency, plant growth and vegetative traits of rubber (Hevea brasiliensis) seedlings grown using different growing media and water levels

The aim of this study was to evaluate the effects of soilless media and water levels on growth and physiological response of rubber plant. The four water levels were I50: 50%, I75: 75%, I100: 100% and I150: 150%) with three replications per water treatment and four soilless media. Water levels were determined as irrigation needed for the root zone in growing media to rise to field capacity I100:100%, at field capacity (FC). The experiment was laid out in randomized complete block design (RCBD) in factorial arrangement 3 x 4 with three replications. Soilless medium contains proportion of vermiculite, perlite, coconut husk, empty fruit bunch (EFB) compose, Christmas Island Rock Phosphate (CIRP), peat moss, urea-N and burnt rice husk coded as M1. Vermiculite, perlite, coconut husk, EFB, CIRP, peat moss, urea-N, sugarcane bagasse coded as M2. M3 is a commercial soilless medium and 100% soil was designated as control. The M1 significantly influenced almost all plant growth traits, noticeable in biomass production. Growth of plants in M1 corresponded to higher water use efficiency WUEinstantaneous and WUEintrinsic, the M1 increased plant growth like LAR, biomass production and root morphological traits. Shoot dry weight of the plant was greater (14.66 g/plant) when 150% was applied and significantly different from M2 (10.36 g/plant), M3 (4.73 g/plant) and M4 6.22 g/plant. Lower water level 50%, applied in plant grown in M1 (31.94 g/plant) recorded highest total shoot fresh weight (SFW). The results showed suitability of the soilless medium M1 and the 50% water level for rubber nursery planting. Consequently, it is recommended for planting where management and control of irrigation water are considered necessary in rubber plantation.

RAD-seq-Based High-Density Linkage Map Construction and QTL Mapping of Biomass-Related Traits in Sorghum using the Japanese Landrace Takakibi NOG

Sorghum [Sorghum bicolor (L.) Moench] grown locally by Japanese farmers is generically termed Takakibi, although its genetic diversity compared with geographically distant varieties or even within Takakibi lines remains unclear. To explore the genomic diversity and genetic traits controlling biomass and other physiological traits in Takakibi, we focused on a landrace, NOG, in this study. Admixture analysis of 460 sorghum accessions revealed that NOG belonged to the subgroup that represented Asian sorghums, and it was only distantly related to American/African accessions including BTx623. In an attempt to dissect major traits related to biomass, we generated a recombinant inbred line (RIL) from a cross between BTx623 and NOG, and we constructed a high-density linkage map based on 3,710 single-nucleotide polymorphisms obtained by restriction-site-associated DNA sequencing of 213 RIL individuals. Consequently, 13 fine quantitative trait loci (QTLs) were detected on chromosomes 2, 3, 6, 7, 8 and 9, which included five QTLs for days to heading, three for plant height (PH) and total shoot fresh weight and two for Brix. Furthermore, we identified two dominant loci for PH as being identical to the previously reported dw1 and dw3. Together, these results corroborate the diversified genome of Japanese Takakibi, while the RIL population and high-density linkage map generated in this study will be useful for dissecting other important traits in sorghum.

The Effect of Pyraclostrobin Application on Yield of Tea (Camelia sinensis (L.) O. Kuntze) under Wet Season

This field experiment aimed to study the effect of pyraclostrobin on tea production and to determine optimum concentration in order to maintain high yield during the period of wet season. The experiment was arranged in Randomized Completely Block Design (RCBD) using single factor and three blocks as replications. The pyraclostrobin doses, consisted of 4 levels, 0, 50, 100, and 150 g.ha-1, each will be tested on three tea clones. Clones tea tested are TRI 2025, Gambung 9 and PGL 15. Data was evaluated for chlorophyll content, photosynthetic rate, number of pecco, number of dormant shoot (banjhi), number of total shoot, pecco fresh weight, banjhi fresh weight, total shoot fresh weight, and shoot dry weight. Data were analysed by using Analysis of Variance (ANOVA) and LSD test at α = 5%. The results informed that pyraclostrobin was able to improve chlorophyll content on TRI 2025 clone, and improved photosynthetic rate on Gambung 9 clone. However, there was no significant different among plants treated with pyraclostrobin on a yield components, i.e., number of pecco, number of banjhi, pecco fresh weight, banjhi fresh weight, total shoot fresh weight, and total shoot dry weight.

The influence of protective netting on tree physiology and fruit quality of apple: A review

Abstract The use of protective netting (also called shade nets or anti-hail nets) is being increasingly adopted in apple (Malus × domestica) production. Protective netting is mainly used to prevent fruit sunburn and protect trees against hail damage. Netting can also be used for protection against damage from birds, fruit bats, insects, wind and sand storms. In recent times, protective nets have been modified into photoselective nets by incorporating chromatic elements into the netting material. These change the spectral characteristics of the solar radiation reaching the tree canopy below the net and can affect physiological pathways that respond to the altered light spectra. Protective netting primarily modifies light quantity and quality underneath by reducing light intensity by an approximately pre-determined percentage. Protective netting has also been reported to reduce wind speed and soil temperature with minimal impact on canopy temperature and relative humidity. Quantifying the influence of protective netting on tree gas exchange has been difficult due to variations in the environmental conditions at the time of measurement. Reductions in light intensity due to protective netting result in increased leaf area, shoot length, and total shoot fresh weight that increases as the net shading percentage increases. Fruit set, return bloom, and flower induction are all affected by protective netting. Ultimately, fruit quality is the critical factor determining whether protective netting is suitable for apple production. The reported results on the effect of protective netting on fruit quality have not been conclusive. It has been suggested that changes in fruit quality under protective netting are often more influenced by the environmental conditions in that specific growing season than the netting itself. For example, typical shade responses under netting can be exacerbated when the natural overall light intensity is reduced on cloudy days. In conclusion, protective netting provides an alternative to traditional approaches to protecting apple from sunburn, mechanical injury from hail and wind, and abiotic stress that limits tree productivity. However, the inconsistent reported results suggest a targeted approach is needed to identify specific physiological responses of apple under protective netting, and more specifically, photoselective netting as a strategy to protect apple orchards from adverse environmental conditions.

Isotopic Labeling of Red Cabbage Anthocyanins with Atmospheric 13CO2

Isotopic labeling of plants provides a unique opportunity for understanding metabolic processes. A significant challenge of isotopic labeling during plant growth is that isotopes must be administered without disrupting plant development and at sufficient levels for mass spectral analysis. We describe a system for isotopic labeling of leafy vegetables with 13C and demonstrate successful incorporation of 13C into anthocyanins of preheading red cabbage (Brassica oleracea L. var. capitata L.). ‘Super Red’ red cabbage seedlings were grown for 34 days in an airtight acrylic labeling chamber supplied with 13CO2 to maintain 400 μL·L−1. Nutrient solution was delivered hydroponically without allowing infusion of natural CO2 into the labeling chamber. Plants were initially grown at 22 °C ± 1 °C in constant light of 228 μmol·m−2·s−1. Upon canopy closure, anthocyanin development was promoted by reducing the nutrient solution concentration and reducing the temperature to 10.5 °C ± 1.5 °C. Total shoot fresh weight (FW) was 1556 g and root FW was 491 g at harvest. Analysis of red cabbage shoot tissue by high-performance liquid chromatography/tandem mass spectrometry indicated the presence of 37 anthocyanins, of which 14 are reported here for the first time. Mass shifts representing 13C incorporation into anthocyanins were evident in mass spectra of anthocyanins from labeled tissue and demonstrate successful isotopic labeling.

Response of mannitol-producing Arabidopsis thaliana to abiotic stress.

In celery, mannitol is a primary photosynthetic product that is associated with celery's exceptional salt tolerance. Arabidopsis plants transformed with celery's mannose-6-phosphate reductase (M6PR) gene produce mannitol and grow normally in the absence of stress. Daily analysis of the increase in growth (fresh and dry weight, leaf number, leaf area per plant and specific leaf weight) over a 12-day period showed less effect of salt (100 mm NaCl) on the M2 transformant than wild type (WT). Following a 12-day treatment of WT, M2 and M5 plants with 100 or 200 mm NaCl the total shoot fresh weight, leaf number, and leaf area were significantly greater in transformants than in WT plants. The efficiency of use of energy for photochemistry by PSII was measured daily under growth conditions. In WT plants treated with 100 mm NaCl, the PSII yield begin decreasing after 6 days with a 50% loss in yield after 12 days, indicating a severe loss in PSII efficiency; whereas, there was no effect on the transformants. Under atmospheric levels of CO2, growth with 200 mm NaCl caused an increase in the substomatal levels of CO2 in WT plants but not in transformants. It also caused a marked decrease in carboxylation efficiency under limiting levels of CO2 in WT compared with transformants. When stress was imposed and growth reduced by withholding water for 12 days, which resulted in a similar decrease in relative water content to salt-treated plants, there were no differences among the genotypes in PSII yields or growth. The results suggest mannitol, which is known to be a compatible solute and antioxidant, protects photosynthesis against salt-related damage to chloroplasts.

Selection of Rosemary (Rosmarinus officinalis L.) Cultivars to Optimize Biomass Yield

SUMMARY Rosmarinus officinalis L. (Labiatae) is a typical shrub of the Mediterranean maquis. In spite of its multiple ornamental and aromatic uses, and the great interest in its cultivation, only a few cultivars or clones have been well characterized. Our breeding program has focused on optimizing biomass yield and improving the quality of cultivated rosemary. In a preliminary phase (1996–1997), 31 mother plants were identified and described in situ throughout Sardinia; spring-shoot samples were then evaluated in laboratory. In a second phase (1996–2000), cuttings of selected clones were planted in a repository at the Experimental Station of the University of Sassari, in central-western Sardinia. In this paper, morphological, biometric, qualitative and phenological characters of fifteen rosemary selections of the repository are reported. Selections tended to produce flowers, fruit and new shoots in various periods of the year. Selections showed a high variability for spring-shoot length, leaf length and width, essential oil content of leaves, and percentage of leaf weight in relation to total shoot fresh weight. Clones with higher leaf/wood ratio and higher essential oil content were considered more suitable for the optimization of biomass yield.

Production And Composition Of Chinese Cabbage Under Plastic Rowcovers In Southern Spain

SummaryThe effects of plastic rowcovers on the growth and quality of Chinese cabbage (Brassica pekinensis (Lour) Rupr. `Nagaoka 50') were investigated in Granada, southern Spain (latitude: 378. 10 9.21 99 N; longitude: 38.38 9 E; .10 99 elevation: 600.m), for three years. Polyethylene (T1) and polypropylene (T2) covers increased air temperature by 7K and 5K, and soil temperature (5- and 15.cm depth) by 3±4K and 2K, respectively, compared with plots in the open (T0). In contrast, radiation levels in T1 and T2 were reduced by 12% to 16%, respectively. Thus, total shoot fresh weight was 111% (T1) and 108% (T2) greater under rowcovers, and the commercial head weights were 105% (T1) and 96% (T2) greater, and dry weights 21% (T1) and 13% (T2) greater than T0. These differences in plant production were reflected in higher yields under plastic, and a higher proportion of marketable heads (23% in open air compared with 68% and 65% under T1 and T2, respectively). The concentration of soluble sugars and pigments were also lower in the shoot under rowcovers than in plants in the open air. There were only small differences between the two plastic covers. Slightly warmer conditions and less shade under polyethylene compared with polypropylene provided greater plant production, yields and sugar concentrations, but lower pigment concentrations. Growing Chinese cabbage plants under plastic rowcovers in southern Spain increased production without significantly affecting composition.

Effect of carbon dioxide enrichment and salinity on photosynthesis and yield in melon

Melon ( Cucumis melo L. Cv Parnon) grown in rockwool culture in the greenhouse was CO 2 enriched, for 5 h every morning, at 400, 800 and 1200 μmol mol −1 and trickle-irrigated with nutrient solutions amended with 0, 25 and 50 mM NaCl. High CO 2 level increased fruit yield, the increase being greater in unsalinated plants than in salinated. With total shoot fresh weight, the increase was greater in salinated plants. CO 2 enrichment also increased leaf growth and the chlorophyll content of the measured leaves. Addition of NaCl in the nutrient solution caused significant reduction in total yield, the reduction being greater at higher concentrations of CO 2. At 25 mM NaCl, the decrease in yield resulted mainly from the smaller fruit size, but at 50 mM yield reduction was due both to smaller fruit size and to fewer fruits per plant. Addition of NaCl caused significant reduction in total shoot fresh weight in all cases, the reduction being greater at the lower level of CO 2. Salinity also, significantly reduced leaf surface irrespective of CO 2 level. Chlorophyll content was reduced by NaCl mainly at the level of 50 mM NaCl. A stronger correlation was found between salinity and shoot fresh weight, plant height and leaf surface area, than salinity and yield and other characteristics. Measurements of gas exchange showed that, for the above mentioned CO 2 and NaCl concentrations, net assimilation was affected by CO 2 to a greater degree than by salinity. Stomatal conductance was most affected by salinity at a concentration of 50 mM NaCl.

Tillers Do Not Influence Phytotoxicity of Imazamethabenz in Wild Oat (Avena fatua)

The response of wild oat to imazamethabenz varies with the growth stage, but the role of tillers in this regard is unclear. Removal of tillers at the three-leaf stage before spraying with imazamethabenz did not significantly affect the total shoot fresh weight measured 3 weeks later. The leaf area and dry weight of intact plants at the three-leaf stage were 17–21% greater than for plants with coleoptilar and first leaf main shoot tillers (T0 and T1) removed. The greater leaf area may have increased herbicide interception per plant. Similar fresh weight reductions in main shoot, total tillers, and total shoots were found whether imazamethabenz was applied to the plant at the two-leaf without tillers or the three-leaf with two tillers stage. Imazamethabenz applied only to the main shoot reduced total shoot dry weight more than an equivalent amount of imazamethabenz applied only to tiller T1 or applied over the whole shoot. Imazamethabenz had the least inhibitory effect on whole plant growth when applied only to T1. When 14C-herbicide was applied to the first main shoot leaf of plants at the three-leaf stage with two tillers, the 14C translocated 38% to roots, 33% to the main shoot, and nearly 30% to all tillers. When 14C-herbicide was applied to the first leaf of T1 then the 14C translocated 50% to T1, 25% to the main shoot, 20% to roots, and 5% to all other tillers. The translocation pattern and fresh weight values suggested that the presence of early tillers during herbicide application neither increased nor decreased imazamethabenz efficacy in wild oat.

Improved micropropagation of Populus spp. by Pluronic F-68

Stem explants and leaves (without petioles) excised from axenic shoots of Populus tremula cv. Ahle or P. tremula × tremuloides cv. Munden were cultured in the presence of the non-ionic, co-polymer surfactant, Pluronic F-68. Stem explants developed shoots within 10 d of culture and significant (p<0.05), but genotype-dependent, increases in total shoot fresh weight (maximum 2 × control) occurred in cultures supplemented with 0.001–0.1% Pluronic F-68 over a 72 d period. Similarly, increases in both fresh weight (up to 10-fold) and number of shoots per P. tremula × tremuloides leaf explant (5-fold maximum) over 60 d occurred with Pluronic F-68 at 0.001%.

Effect of decapitation on absorption, translocation, and phytotoxicity of imazamethabenz in wild oat (Avena fatua L.)

The release of apical dominance by the physical destruction in situ of the apical meristem and associated leaf primordia (decapitation) promoted the growth of tillers in non-herbicide-treated wild oat plants, as indicated by increased tiller lengths and fresh weights. At 96 h after [14C] herbicide treatment following decapitation, the absorption of [14C]imazamethabenz and total translocation of radioactivity were respectively increased by 28% and 49%. By 96 h after [14C]imazamethabenz application, the radioactivity detected in the roots of decapitated plants was 45% higher than that in the roots of nondecapitated plants while the radioactivity in tillers of decapitated plants was 2.6-fold that in tillers of intact plants. Decapitation together with foliar spraying of imazamethabenz at 200 g ha−1 further reduced tiller fresh weight, greatly decreased the total tiller number, and thereafter significantly increased overall phytotoxicity by 32% as measured by total shoot fresh weight. The results of this study support the hypothesis that main shoot apical dominance limits translocation of applied imazamethabenz to lateral shoots, rendering tillers less susceptible to growth inhibition by the herbicide.

Nitrate Reductase Activity and Nitrate Concentration in Cotton Plant Leaf Blades and Petioles

AbstractGreenhouse studies were conducted to determine the potential of nitrate reductase activity (NRA) as an indicator of the change of N concentration of cotton (Gossypium hirsutum L.) shoots. The results showed that cotton petiole in vivo NRA was not significantly different from NRA in leaf blades during vegetative growth. Nitrate reductase activity (in vivo) in cotton petioles was significantly higher than in leaf blades during reproductive growth. When plants were in the three‐mature‐leaf stage, petiole NRA contributed 16% of total cotton shoot NRA. The petiole biomass was 14% of total shoot fresh weight and 8% of total shoot dry weight. Petiole NRA of plants in the vegetative growth stage increased from 39 to 68 pmol NO−2 g1− FW (fresh weight) s−1 when supplemented with nitrate‐N. These results indicate that cotton petiole NRA is significant and its assay has potential for incorporation into monitoring systems that determine the change of N concentration in cotton shoots.