Increased Leaf Yield Research Articles

Consecutive Pruning Enhances Leaf Flavonoids, Leaf Yield, and Cutting Rooting in Ginkgo biloba

Ginkgo biloba L. is a valuable medicinal plant known for its high content of flavonoids and terpenoids in the leaves of young trees. Pruning can increase leaf yield in ginkgo plantations; however, it is unclear how the intensity of pruning affects leaf yield and quality. In addition, G. biloba exhibits low cutting rooting rates, which limits its efficiency in asexual propagation. In our study, we compared consecutive pruning with varying levels of intensity, including top pruning, light pruning, and heavy pruning, to evaluate the effects of pruning on leaf yield and cutting rooting. The results showed that these three pruning methods all contributed to an increase in the number of new branches, the leaf weight, and the flavonoid content in five-year-old trees. Among them, the effect of light pruning was the best, with a 150% increase in branch number, a 130% increase in leaf weight, and a 40.6% increase in flavonoid content. The secondary pruning further increased leaf area by 22.3%, indicating that secondary pruning further enhanced the rejuvenation of plants and increased leaf yield. At the transcriptional level, pruning can significantly change the expression of genes related to bud sprouting, resulting in a particularly significant increase in SHR expression in the buds. Pruning also promoted the expression of important genes related to flavonoid synthesis, including chalcone synthase (CHS), flavonoid 3′-hydroxylase (F3′H), flavonol synthase (FLS), and dihydroflavonol reductase (DFR). Furthermore, we demonstrated a significant increase in the rooting rate of these second-pruned branch cuttings and screened the optimal hormone ratio for rooting, which is 1.5 μM MeJA + 400 mg/L NAA + 100 mg/L Uniconazole-P. These results suggest that secondary pruning can effectively rejuvenate plants to promote cutting rooting in G. biloba. This method can not only be used to improve the yield and quality of ginkgo leaves, but also for cutting propagation.

The Effects of Transplanting Date on Management of Tobacco Insect Pests. Min review

The main review purpose this paper provides updated information on the effect of different transplanting dates on the infestation of tobacco insect pets were carried out at different location by different Scholars. The results revealed that different trials conducted in different agro ecological zone indicated that damage was higher and green leaves yield decrease were in late transplanted tobacco. While, the damage was gradually decrease and green leaves yield increase in early transplanted tobacco. Numerous species of insect pests of tobacco affect the crop in the field, in the greenhouse, and in storage. The effect tobacco insect pests reduced green leaf yield, quality and damage roots, leaves, buds parts of plants and others transmit several important tobacco disease pathogens. As management systems for flue-cured tobacco (Nicotiana tabacum L.) used different transplanting date were compared to evaluate their influence on insect pests’ damage, leaves yield and quality of flue-cured tobacco. The results indicated that early transplanted significantly increase leaf yield, growth parameters and decrease insect pest damage incidence. The study indicated that transplanted has pronounced positive effect on management of tobacco insect pests and growth of tobacco.

Métodos de inoculação de Azospirillum brasilense em alface e rúcula em sistema hidropônico

ABSTRACT: Lettuce and arugula are the most cultivated leafy vegetables in hydroponic systems in the world, and the little information about Azospirillum brasilense effects in research in this system makes it necessary to verify the best method of inoculation of these bacteria. Therefore, this study aimed to verify the beneficial effects of inoculation methods of A. brasilense on plant growth and nutrition of lettuce and arugula grown in the hydroponic system. The study was conducted in a greenhouse with 30% shading. A randomized block design with five replicates in a 4 × 2 factorial scheme was used. Four A. brasilense inoculation methods (non-inoculated, foliar application, nutrient solution, and nutrient solution + foliar application) and two leafy vegetable species - arugula and lettuce - were evaluated. All inoculation methods improved plant height, shoot fresh and dry mass, root fresh and dry mass, fresh leaf yield, leaf chlorophyll index, accumulation of nitrogen, potassium, calcium, sulfur, phosphorus, iron, manganese, and copper and reduced nitrate accumulation in shoot and root of arugula and lettuce. Inoculation via nutrient solution + foliar application of A. brasilense is the most suitable for hydroponic arugula cultivation because it provides greater fresh leaf yield. All inoculation methods increased leaf yield in hydroponic lettuce. Hydroponic arugula and lettuce plants showed greater accumulation of nutrients and plant growth with less nitrate accumulation in the shoot under inoculation with A. brasilense.

Effect of Fungicide Protection of Sugar Beet Leaves (Beta vulgaris L.): Results of Many Years Experiments

The rosette is the above-ground morphological part of sugar beet in the first year of its ontogenesis. The size and health of the leaves determine photosynthesis and the production of sugars and their redistribution throughout the plant and thus the yields and quality of individual organs. One means of protecting leaves is to apply fungicides. Their efficacy and effects of use depend on, among other things, the active ingredient and number of sprayings, as well as environmental conditions. The aim of the 11-year study was to evaluate the effect that the foliar application of fungicides in sugar beet cultivation had on leaf infestation and damage, the Leaf Area Index (LAI), leaf yield, and a plant foliage index (FI) expressed as the ratio of leaf mass to root mass. In field experiments, six treatments were compared: a control without fungicides; three sprayings with triazoles, benzimidazoles, and strobilurins as the active ingredients; and a single application of tebuconazole, epoxiconazole, strobilurin, and an epoxiconazole + thiophanate-methyl mixture. The efficacy and effects of the fungicide protection depended on its method of application and environmental conditions. Applying fungicides weakened the positive correlation of sugar beet leaf infestation and leaf damage to the sum of precipitation relative to the unprotected plants. In ten of the eleven years of the study, fungicide protection significantly increased leaf yields of plants and decreased their FI. In only three years did three sprayings increase leaf yield more than single sprayings, and, in six years, at least one of the active ingredients or the epoxiconazole + thiophanate-methyl mixture was as effective as triple sprayings. It is therefore warranted to permanently monitor the condition of plants and to select the fungicide application method depending on conditions.

Effect of inoculation methods of Azospirillum brasilense on growth and yield of lettuce in the hydroponic system

Lettuce (Lactuca sativa L.) is one of the most popular and economically critically leafy vegetable crops in the world. Nevertheless, the existing studies offered information limited on the Azospirillum brasilense effects in this research system makes it necessary to verify the best method of inoculation for these bacteria. Currently, a variety of techniques for producing Lettuce have been investigated, including soilless aeroponic, hydroponic, and deep-water culture systems. Therefore, this study aimed to verify the beneficial effects of inoculation methods of A. brasilense on plant growth and nutrition of two lettuce cultivars grown in the hydroponic system. The study was conducted in a greenhouse with 30% shading at Vietnam National University of Forestry – Dong Nai campus, Trang Bom district, Dong Nai province. A randomized block design with three replicates in a 4 × 2 factorial scheme was used. Four A. brasilense inoculation methods (non-inoculated, foliar application, nutrient solution, and nutrient solution + foliar application) and two lettuce cultivars were evaluated. All inoculation methods improved plant height, shoot fresh and dry mass, fresh leaf yield, and accumulation of potassium, calcium, phosphorus, iron, manganese, and copper. Inoculation via nutrient solution + foliar application of A. brasilense is the most suitable for hydroponic lettuce GR-607 cultivation because it provides greater fresh leaf yield. All inoculation methods increased leaf yield in hydroponic lettuce.

Development of late-bolting plants by CRISPR/Cas9-mediated genome editing from mesophyll protoplasts of lettuce.

CRISPR/Cas9-mediated introduction of a single base mutation in SOC1, a transcription factor that regulates flowering time, results in late-bolting phenotypes in lettuce. Lettuce is a widely consumed leafy vegetable crop. One of the molecular approaches that can increase leaf yield of lettuce is to delay the onset of flowering. Flowering time or time-to-bolting is not only a valuable trait for lettuce, but also a sought-after phenotype for other leafy vegetable crops. This is because delayed flowering enables more extensive vegetative growth, which leads to higher leaf numbers, and possibly larger leaves. Here, we deployed the most recent gene-editing technique to reduce the expression of SOC1, which is a gene that encodes one of several transcription factors that regulate the onset of flowering in plants. By inducing a single base mutation in SOC1 through Cas9 protein-gRNA ribonucleoproteins (RNPs) system, we showed that the time to first flower bud formation in lettuce is longer than that of wild type. In addition, expression of the floral regulatory genes including LsLFY, LsFUL, LsAPL1, and LsAPL2, was lower in the SOC1 gene edited plants than that of the wild type. The gene-editing technique established in this study could be directly applied for diverse quality improvement of lettuce by direct RNP transfer from protoplasts. Furthermore, it is expected that direct RNP transfer from protoplasts can be used as a useful mean for developing various gene edited crops.

The Effects of Preharvest Mild Shading on the Quality and Production of Essential Oil from Kaffir Lime Leaves (Citrus hystrix)

Kaffir lime (Citrus hystrix DC) is a less popular citrus species commonly used as a food spice and a source of essential oil. Early studies report the success of preharvest mild shading to increase leaf yield, although there is still limited information on the effect of preharvest shading on the quality of essential oil produced. The aim of this current study is to evaluate the effect of preharvest mild shading factors on the yield, physical characteristics, and metabolite fingerprinting of kaffir lime leaves essential oil (KLLEO). One-year-old kaffir lime trees were sampled in two preharvest treatments, i.e., open sun and mild shading (24% light reduction) at Pasir Kuda experimental field, Bogor, Indonesia. Statistical analysis showed that there was no significant effect of preharvest treatment on yield and physical characteristics (color, specific gravity, and refractive index) of KLLEO. In contrast, there was a metabolite fingerprinting variation of KLLEO as an effect of mild shading. The relative percentage of bergamol, citronellol, caryophyllene oxide, citronellic acid, isopulegol, isopulegyl formate, limonene, linalool, and linalool oxide was increased by mild shading. On the other hand, the main metabolite (citronellal) was significantly reduced by about 10% in shading treatment, as compared to the open-sun ones.

Response of Aloe vera to potassium fertilization in relation to leaf biomass yield, its uptake and requirement, critical concentration and use efficiency

Increasing crop yield and fertilizer use efficiency with optimum potassium (K) addition is essential for sustainable crop production. With the aim of establishing a scientific basis of K fertilization on the growth, leaf biomass yield, K requirement, K use efficiency, and critical leaf K concentration of Aloe vera, a pot experiment was carried out at farmer’s field with six levels of K viz. 0, 40, 60, 80, 120, and 160 kg ha−1 following completely randomized design. Yield attributes and leaf yield were significantly influenced by K application rate and the best results were obtained from the application of 120 kg K ha−1. On an average, application of K increased leaf yield by 105% compared to control. The highest gel weight and economic profit was obtained from K120. On the other hand, the highest leaf K concentration and uptake were found with the addition of 160 kg K ha−1. The higher K uptake and yield contributed to the enhanced K use efficiency of Aloe vera. The correlation results suggest a significant contribution of K on the growth parameters and increased leaf yield as well. The calculated K requirement for 80% leaf biomass and the critical leaf K concentration were 72.5 kg ha−1 and 1.29%, respectively.

Phosphorous Use Efficiency and Its Requirement for Aloe Vera Cultivated on Silty Loam Soils

ABSTRACT Balanced application of phosphorus (P) fertilizer is important for productive agricultural systems with a reduced environmental footprint. This study aimed to assess the effect of P on the leaf yield, P use efficiency, P concentration and uptake by Aloe vera. A pot trial experiment was conducted using a completely randomized design, with six levels of P applied at 0, 30, 45, 60, 80, and 120 kg ha−1, replicated in triplicate. The results revealed that yield attributes, leaf yield, P concentration and uptake were significantly improved with P application and optimum results were obtained when P was applied at 80 kg ha−1. The addition of P increased leaf yield by 33 to 91% compared to the untreated control. Likewise, the highest numbers of suckers, leaves, fresh and dry gel weight, and profit based on benefit cost ratio was recorded with this treatment. In contrast, the highest P concentration and uptake by the leaf were observed at the highest P treatment rate of 120 kg ha−1. The highest plant height, leaf area and fresh gel weight were responsible for the production of higher leaf yield. The minimum amount of P for 80% leaf biomass production was estimated to be 43.9 kg ha−1 whereas the critical leaf P concentration was 0.62% for Aloe vera cultivation. The result suggests that application of 80 kg P ha−1 could produce economically higher yield of A. vera, and further investigation is now required to validate these results for other soil types under field conditions.

Arthropod entrapment increases specialist predators on a sticky crop and reduces damage

Maximizing plant defensive strategies is integral to effective integrated pest management. Direct defenses, in the form of chemical and morphological components that inhibit pest damage, underlie host plant resistance, while indirect defenses including food provisioning and semiochemical production, improve biological control. Interactions between the two defensive strategies may be disruptive, complementary, or synergistic and are an important consideration for effective pest management programs. Glandular trichomes are plant structures that inhibit or entrap arthropods, protecting plants against herbivores, potentially at the cost of reducing natural enemy efficacy. Glandular trichomes may also contribute to indirect defense, as predatory arthropods adapted to “sticky” surfaces scavenge on entrapped arthropods. Scavenging increases predator abundance and reduces plant damage; this protective mutualism has been demonstrated with multiple sticky wild flowers but has not been assessed in an economically important plant, such as tobacco. We augmented dead arthropods (carrion) on tobacco plants grown under conditions similar to commercial production and assessed tri-trophic interactions. Carrion augmentation increased predator abundance, reduced damage to reproductive structures, and increased leaf yield, but did not reduce pest densities. We determined that systemic insecticide use did not affect carrion entrapment on tobacco plants. Review of the literature revealed that a variety of economically important plants entrap arthropods on their surfaces, indicating this mutualism has potential for development into a conservation biological control tactic.

Effects of nitrogen fertilizer doses on growth and yield of Java lemongrass (Cymbopogon winterianus Jawitt) in Gia Lai province

Java lemongrass is commonly cultivated in Vietnam for the food industry and traditional medicine. To achieve high productivity, the application of fertilizer is one of the most traditional farm practices and necessary. A single factorial experiment was carried out in a randomized complete block design to investigate the effect of nitrogen fertilizer doses on growth, leaf and essential oil yields of Java lemongrass. Eight treatments were used in this experiment including 0, 15, 30, 45, 60, 75, 90 kg N/ha and applying only 2 tons Komic biofertilizer/ha as control. Fertilizer foundation for treatments 1 - 7 (for 1 ha) included 2 tons of Komix biofertilizer, 60 kg P2O5 and 60 kg K2O. The application of 90 kg N/ha significantly improved the growth of Java lemongrass and increased leaf yield (12.02 tons/ha/3 harvest times) as well as resulted in the highest oil yield (138.1 kg/ha/3 harvest times).

Evaluation of Genomic DNA-Extraction Methods for Molecular Analysis of Solanecio biafrae

ABSTRACT Solanecio biafrae (Oliv. & Hiern) C. Jеffrеу, an indigenous vegetable of the humid tropics, is rich in minerals and easy to cultivate, but its vegetative growth is slow, making production fall short of demand. An efficient and effective genomic DNA-extraction method is necessary for a comprehensive molecular analysis to increase leaf yield and further improve proximate and mineral contents of the vegetable. Cetyltrimethylammonium bromide (CTAB), sodium dodecyl sulfate (SDS), and Qiagen kit (QIAGEN) methods were evaluated for extraction of genomic DNA from young leaves suitable for PCR amplification for molecular analyses. Quantity and quality of the DNA were examined spectrophotometerically and with gel electrophoresis. Amplification of the DNA by PCR for molecular analysis was assessed with five inter-simple sequence repeat (ISSR) primers. The mean DNA yield using QIAGEN, CTAB, and SDS methods were 71.0, 35.4, and 38.8 µg∙µL−1∙g−1 of tissue, respectively. The mean 260/280 nm ratios of QIAGEN, CTAB, and SDS were 1.84, 1.83, and 1.79, respectively. Gel electrophoresis indicated presence of DNA free of contaminants in all samples using three methods. A total of 270 distinct bands were produced by five ISSR primers with similar patterns among three DNA-extraction methods, ranging from 200–2900 base pairs. Three methods are capable of extracting adequate genomic DNA suitable for PCR amplification. The QIAGEN method produced the highest DNA yield, which was of the same quality with DNA obtained using CTAB and SDS methods.

Poultry Feather Meal Application in Organic Flue‐Cured Tobacco Production

Core Ideas Poultry feather meal is acceptable in organic flue‐cured tobacco production. Application rates of organic N should reflect those in conventional production. Soil moisture is critical for N mineralization and assimilation. Information on N management in organic flue‐cured tobacco production is limited. Research was conducted from 2012–2013 to determine the effects of two certified organic N sources applied at three rates on the yield, quality, and chemical constituents of flue‐cured tobacco. These organic N sources included Nature Safe 13–0–0 (NS) and Nutrimax 12–1–0 (NM), both of which consisted of hydrolyzed poultry feather meal. Application rates for both fertilizer sources were 17 kg N ha−1 above recommendation (B+), at recommendation (B), and 17 kg N ha−1 below recommendation (B–). A conventional control containing urea‐ammonium‐nitrate (UAN) was applied at the B application rate. Tobacco yield and quality were similar among conventional and organic N programs. Leaf N concentration, SPAD measurements at flowering, and total alkaloid concentration of cured leaves responded positively to increased N application rates, regardless of organic fertilizer source. The largest increases in nitrogenous‐based leaf constituents were observed in this study where B+ treatments were applied; however, those increases did not translate into increased leaf yield or quality and could delay the initiation of leaf senescence in growing seasons with low soil moisture. Results from this study demonstrate the acceptability of poultry feather meal sources for organic tobacco production, and confirm that application rates of organic N sources should follow conventional recommendations.

Evaluation of poison baits against Spodoptera litura Fab. (Lepidoptera: Noctuidae) in spinach

Choice tests were conducted under laboratory condition to standardize food bait using larvae of S. litura revealed the combination of rice bran + jaggery 20% + yeast 0.1% and rice bran + molasses 10% have proved best in attracting more larval populations. Efficacy of different combinations of poison baits was evaluated under field condition for the management of cutworm population in spinach. The jaggery based bait mixed with spinosad (rice bran + jaggery 20% + yeast 0.1% + spinosad @ 2.5ml/kg) proved best next to spinosad spray in reducing the larval population and leaf damage and thereby increased leaf yield over other baits and untreated control. Hence, jaggery based bait with spinosad may be recommended for management of cutworms in vegetable ecosystem.

Yielding of leaf celery Apium graveolens L. var. secalinum Alef. depending on the number of harvests and irrigation

Leaf celery (Apium graveolens var. secalinum) is a vegetable with medicinal and spicy properties. Its numerous intensely fragrant leaves can be cut several times during the plant growing period. The aim of this study was to evaluate the effect of irrigation and number of harvests on leaf celery yield of the cultivars ‘Afina’ and ‘Gewone Snij’. Plant irrigation significantly increased leaf yield and plant height of leaf celery. Higher total yield was obtained from non-irrigated plants when leaves were harvested three times, whereas for irrigated plants yield was higher in the case of two leaf harvests. Irrespective of the experimental factors, higher yield was obtained from the cultivar ‘Gewone Snij’.

The effect of foliar feeding of potassium salts and urea in spinach on gas exchange, leaf yield and quality

In a pot experiment conducted in a phytotron, the effectiveness of foliar feeding of different potassium salts, with and without the addition of 0.5% CO(NH<sub>2</sub>)<sub>2</sub>, in spinach (<i>Spinacia oleracea</i> L.) was investigated. Potassium was applied 3 times in the form of 1% solutions KCl, KNO<sub>3</sub>, K<sub>2</sub>SO<sub>4</sub> and C<sub>6</sub>H<sub>5</sub>K<sub>3</sub>O<sub>7</sub>•H<sub>2</sub>O, compared to water as the control treatment. The obtained results show that foliar feeding of potassium salts in spinach is an efficient method of supplementing the level of K<sup>+</sup> in plants during vegetation. Plants fed with KNO<sub>3</sub> had the highest content of potassium in leaves, and those fertilized with K<sub>2</sub>SO<sub>4</sub>, C<sub>6</sub>H<sub>5</sub>K<sub>3</sub>O<sub>7</sub> × H<sub>2</sub>O and KCl had an only slightly lower potassium content. The application of potassium salts resulted in more intensive gas exchange in leaves (stomatal conductance, photosynthesis, transpiration) and, as a consequence of that, increased leaf yield. Potassium nitrate and citrate influenced most effectively the abovementioned processes. The treatment of spinach with potassium salts resulted in an increased content of protein, chlorophyll, carotenoids, nitrates and iron as well as a decreased content of vitamin C and calcium in leaves.

BIOCONTROL OF ROOT KNOT NEMATODE, MELOIDOGYNE INCOGNITA (KOFOID AND WHITE) CHITWOOD IN MULBERRY (MORUS ALBA L.)

ABSTRACT Field experiments conducted for the evaluation of efficacy of biocontrol agents viz., Pseudomonas fluorescens and Trichoderma viride, against root knot nematode, Meloidogyne incognita in mulberry (V1 variety) revealed that soil application of both P. fluorescens and T. viride alone or in combination was able to control the nematode population and improve the mulberry leaf yield and nutritional standards. Combined soil application of P. fluorescens (@ 10 g/plant) + T. viride (@ 10 g/plant) as soil application was effective to check the root knot nematode disease and to improve growth of mulberry with increased leaf yield and reduced nematode population.

Mulberry nutrient management for silk production in Hubei Province of China

AbstractThe silk industry is important for south China's rural economy. Leaves of mulberry (Morus spp.) are used for silkworm production. Hubei province is one of the main silk‐producing provinces in China. The objectives of this research were to survey the fertilization practices in the mulberry‐producing regions in the province and to determine the best nutrition‐management practice for mulberry plantations. A survey and a series of field experiments with N, P, K, and micronutrients were conducted from 2001 to 2002. In addition, a silkworm‐growth experiment was also conducted by feeding leaves harvested from various fertilization treatments. The results indicate that poor soil fertility and unbalanced fertilization were the main factors limiting mulberry‐leaf yield and quality in Hubei province. Nitrogen fertilization of mulberry has reached a high level (454 kg ha–1 y–1) in Hubei province, but P‐ and K‐fertilization rates have not been matched with N‐fertilization rates as farmers are not aware of the significance of P and K. Balanced fertilization showed positive nutrient interactions with respect to mulberry yield and quality. Potassium application increased yield and quality (protein and sugar concentration) of mulberry leaves. Silkworm growth and cocoon quality were improved when silkworms were fed with the leaves derived from K‐fertilized plants in comparison with those taken from control plots. Application of Mg, S, and B also significantly improved leaf sugar, essential and total amino acid concentrations, but did not increase leaf yield significantly. It is concluded that a fertilizer dose of 375 kg N ha–1, 66 kg P ha–1, and 125 kg K ha–1 is suitable for the cultivation of mulberry in the Hubei province along with Mg, S, and B, wherever necessary, for the improvement of yield and quality of mulberry leaves.

Reaction of Leaf Celery (Apium Graveolens L. Var. Secalinum) To Planting Density and Irrigation

Reaction of Leaf Celery (Apium Graveolens L. Var. Secalinum) To Planting Density and Irrigation In experiments conducted in the years 2004-2005, effect of seedlings planting density and irrigation on yield of 2 cultivars of leaf celery (Afina, Safir) was evaluated. Transplants were planted on 15 May 2004 and 12 May 2005 with spacing 25 x 20 cm and 15 x 20 cm. Harvest of celery leaves was carried out in three turns: on 15 July, 14-15 September and 27-28 October. It was shown that higher planting density significantly increases yield of leaves. Irrigation increased leaf yield, on average, by 55.9%. Depending on cultivar and planting density, leaf yield of non-irrigated plants was 5.29-6.34 kg.m-2, while for irrigated plants it ranged from 7.70 to 11.97 kg.m-2.

Influence of Lime and Macronutrients on Flue-cured Tobacco in Malaysian Tropical Peat

SUMMARYOn unlimed Malaysian peat (pH 3.5), flue-cured tobacco produced negligible leaf yields and showed no response to urea. Liming up to pH 5.25 (32 t/ha lime) linearly increased leaf yield. Tobacco responded linearly without reduced leaf quality to 90 k/ha N at pH 4.01 (8 t/ha lime), but to 45 kg/ha N at pH 4.40–5.25 (16–32 t/ha lime), higher N rates at the respective liming levels producing leaves of lower quality. The optimum rates of P and K for flue-cured tobacco appeared to be 26 and 186 kg/ha respectively, with linear responses up to those rates.