scholarly journals Estimation of Evapotranspiration and Crop Coefficient of Rain-Fed Tea Plants under a Subtropical Climate

Agronomy ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 2332
Author(s):  
Shenghong Zheng ◽  
Kang Ni ◽  
Lingfei Ji ◽  
Chenguang Zhao ◽  
Hongling Chai ◽  
...  
Keyword(s):  
Plant Growth ◽  
Crop Coefficient ◽  
Experimental Period ◽  
Irrigation Scheduling ◽  
Subtropical Climate ◽  
Strong Basis ◽  
Tea Plantation ◽  
Demand Prediction ◽  
Tea Plantations ◽  
A Minor

Crop coefficient (Kc) is one of the most significant parameters for crop water demand prediction and irrigation scheduling. However, there is a lack of knowledge about water vapor and Kc in tea plantation ecosystems. This study explored and determined the actual evapotranspiration (ETc) and Kc of two cultivars of tea (Camellia sinensis), clone variety Baiye1 (BY1) and Longjing43 (LJ43), based on lysimeter data. An estimation was made for both for ETc and adjusted ETc, and the corresponding Kc and adjusted Kc. The results showed that the adjusted ETc and Kc values revealed a minor fluctuation when compared to the ETc and Kc values during the experimental period, which indicated that the adjusted ETc and Kc values were more precise and practical to field conditions. The average adjusted Kc values were 0.71 (range of 0.43–1.02) for BY1 and 0.84 (range of 0.48–1.22) for LJ43. Additionally, heavy pruning can decrease ETc and Kc values, possibly due to the lower level of LAI after pruning. Moreover, it is clearly manifested that BY1 consistently had lower ETc and Kc values than those of LJ43 because of plant growth status differences between BY1 and LJ43. Overall, our study proposed a reliable reference of Kc in tea plantation, and illuminated the effects of pruning and plant growth differences on Kc, which could provide a strong basis for precise irrigation in tea plantations in a subtropical climate.

scholarly journals Effect of different levels of humic acids on the nutrient content, plant growth, and soil properties under conditions of salinity

2011 ◽  
Vol 6 (No. 1) ◽  
pp. 21-29 ◽  
Author(s):  
H. Khaled ◽  
H.A. Fawy
Keyword(s):  
Plant Growth ◽  
Humic Substances ◽  
Humic Acids ◽  
Foliar Application ◽  
N Uptake ◽  
Seedling Emergence ◽  
Dry Weight ◽  
Nutrient Content ◽  
Nutrient Elements ◽  
A Minor

In this study, the effects were investigated of salinity, foliar and soil applications of humic substances on the growth and mineral nutrients uptake of Corn (Hagein, Fardy10), and the comparison was carried out of the soil and foliar applications of humic acid treatments at different NaCl levels. Soil organic contents are one of the most important parts that they directly affect the soil fertility and textures with their complex and heterogenous structures although they occupy a minor percentage of the soil weight. Humic acids are an important soil component that can improve nutrient availability and impact on other important chemical, biological, and physical properties of soils. The effects of foliar and soil applications of humic substances on the plant growth and some nutrient elements uptake of Corn (Hagein, Fardy10) grown at various salt concentrations were examined. Sodium chloride was added to the soil to obtain 20 and 60mM saline conditions. Solid humus was applied to the soil one month before planting and liquid humic acids were sprayed on the leaves twice on 20<sup>th</sup> and 40<sup>th</sup> day after seedling emergence. The application doses of solid humus were 0, 2 and 4 g/kg and those of liquid humic acids were 0, 0.1 and 0.2%. Salinity negatively affected the growth of corn; it also decreased the dry weight and the uptake of nutrient elements except for Na and Mn. Soil application of humus increased the N uptake of corn while foliar application of humic acids increased the uptake of P, K, Mg,Na,Cu and Zn. Although the effect of interaction between salt and soil humus application was found statistically significant, the interaction effect between salt and foliar humic acids treatment was not found significant. Under salt stress, the first doses of both soil and foliar application of humic substances increased the uptake of nutrients.

scholarly journals THE WATER RELATIONS AND IRRIGATION REQUIREMENTS OF SUGAR CANE (SACCHARUM OFFICINARUM): A REVIEW

2011 ◽  
Vol 47 (1) ◽  
pp. 1-25 ◽  
Author(s):  
M. K. V. CARR ◽  
J. W. KNOX
Keyword(s):  
Water Stress ◽  
Water Relations ◽  
Sugar Cane ◽  
Root Zone ◽  
Water Productivity ◽  
Crop Coefficient ◽  
Saccharum Officinarum ◽  
Irrigation Scheduling ◽  
Background Information ◽  
Technology Choice

SUMMARYThe results of research on the water relations and irrigation needs of sugar cane are collated and summarized in an attempt to link fundamental studies on crop physiology to irrigation practices. Background information on the centres of production of sugar cane is followed by reviews of (1) crop development, including roots; (2) plant water relations; (3) crop water requirements; (4) water productivity; (5) irrigation systems and (6) irrigation scheduling. The majority of the recent research published in the international literature has been conducted in Australia and southern Africa. Leaf/stem extension is a more sensitive indicator of the onset of water stress than stomatal conductance or photosynthesis. Possible mechanisms by which cultivars differ in their responses to drought have been described. Roots extend in depth at rates of 5–18 mm d−1 reaching maximum depths of > 4 m in ca. 300 d providing there are no physical restrictions. The Penman-Monteith equation and the USWB Class A pan both give good estimates of reference crop evapotranspiration (ETo). The corresponding values for the crop coefficient (Kc) are 0.4 (initial stage), 1.25 (peak season) and 0.75 (drying off phase). On an annual basis, the total water-use (ETc) is in the range 1100–1800 mm, with peak daily rates of 6–15 mm d−1. There is a linear relationship between cane/sucrose yields and actual evapotranspiration (ETc) over the season, with slopes of about 100 (cane) and 13 (sugar) kg (ha mm)−1 (but variable). Water stress during tillering need not result in a loss in yield because of compensatory growth on re-watering. Water can be withheld prior to harvest for periods of time up to the equivalent of twice the depth of available water in the root zone. As alternatives to traditional furrow irrigation, drag-line sprinklers and centre pivots have several advantages, such as allowing the application of small quantities of water at frequent intervals. Drip irrigation should only be contemplated when there are well-organized management systems in place. Methods for scheduling irrigation are summarized and the reasons for their limited uptake considered. In conclusion, the ‘drivers for change’, including the need for improved environmental protection, influencing technology choice if irrigated sugar cane production is to be sustainable are summarized.

scholarly journals Evaluating On-demand Irrigation Systems for Container-grown Woody Plants Grown in Biochar-amended Pine Bark

HortScience ◽  
2018 ◽  
Vol 53 (12) ◽  
pp. 1891-1896 ◽  
Author(s):  
Nastaran Basiri Jahromi ◽  
Amy Fulcher ◽  
Forbes Walker ◽  
James Altland ◽  
Wesley Wright ◽  
...  
Keyword(s):  
Plant Growth ◽  
Moisture Content ◽  
Water Use ◽  
Dry Weight ◽  
Irrigation Scheduling ◽  
Total Water ◽  
On Demand ◽  
Substrate Moisture ◽  
Silver Dollar ◽  
Conventional Irrigation

Controlling irrigation using timers or manually operated systems is the most common irrigation scheduling method in outdoor container production systems. Improving irrigation efficiency can be achieved by scheduling irrigation based on plant water needs and the appropriate use of sensors rather than relying on periodically adjusting irrigation volume based on perceived water needs. Substrate amendments such as biochar, a carbon (C)-rich by-product of pyrolysis or gasification, can increase the amount of available water and improve irrigation efficiency and plant growth. Previous work examined two on-demand irrigation schedules in controlled indoor (greenhouse) environments. The goal of this study was to evaluate the impact of these on-demand irrigation schedules and hardwood biochar on water use and biomass gain of container-grown Hydrangea paniculata ‘Silver Dollar’ in a typical outdoor nursery production environment. Eighteen independently controlled irrigation zones were designed to test three irrigation schedules on ‘Silver Dollar’ hydrangea grown in pine bark amended with 0% or 25% hardwood biochar. The three irrigation schedules were conventional irrigation and two on-demand schedules, which were based on substrate physical properties or plant physiology. Conventional irrigation delivered 1.8 cm water in one event each day. The scheduling of substrate-based irrigation was based on the soilless substrate moisture characteristic curve, applying water whenever the substrate water content corresponding to a substrate water potential of –10 kPa was reached. The plant-based irrigation schedule was based on a specific substrate moisture content derived from a previously defined relationship between substrate moisture content and photosynthetic rate, maintaining the volumetric water content (VWC) to support photosynthesis at 90% of the maximum predicted photosynthetic rate. Total water use for the substrate-based irrigation was the same as for the conventional system; the plant-based system used significantly less water. However, plant dry weight was 22% and 15% greater, water use efficiency (WUE) was 40% and 40% greater, and total leachate volume was 25% and 30% less for the substrate-based and plant-based irrigation scheduling systems, respectively, than for conventional irrigation. The 25% biochar amendment rate reduced leachate volume per irrigation event, and leaching fraction, but did not affect total water use or plant dry weight. This research demonstrated that on-demand irrigation scheduling that is plant based or substrate based could be an effective approach to increase WUE for container-grown nursery crops without affecting plant growth negatively.

Cover Crops Enhance Natural Enemies While Help Suppressing Pests in a Tea Plantation

2019 ◽  
Vol 112 (4) ◽  
pp. 348-355 ◽  
Author(s):  
Li-Lin Chen ◽  
Pei Yuan ◽  
Min-Sheng You ◽  
Gabor Pozsgai ◽  
Xu Ma ◽  
...  
Keyword(s):  
Species Richness ◽  
Cover Crops ◽  
Beneficial Arthropods ◽  
Vigna Sinensis ◽  
Free Products ◽  
Tea Plantation ◽  
Tea Plantations ◽  
Trifolium Repens L ◽  
Arthropod Biodiversity ◽  
Sustainable Pest Control

Abstract Tea is an economically important crop, consumed by billions of people. Despite the increasing market for pesticide-free products, the use of pesticide in tea is still high. In order to investigate whether intercropping promotes biological control organisms, Chamaecrista rotundifolia (Pers.) Greene, Indigofera hendecaphylla Jacq., Trifolium repens L., and Vigna sinensis (L.) were separately intercropped with free weeding as control in a tea plantation at Yangli, China. Arthropods were collected by taking sweep-net samples, and treatment effects on assemblages were investigated. The combined species richness of all arthropods and that of parasitoids was significantly increased in intercropped treatments while the species richness of herbivores and predators was only greater in C. rotundifolia and I. hendecaphylla intercropped treatments. Compared with control, the combined abundance of all arthropods, and that of herbivores was lower, while the abundance of parasitoids and its taxa was greater in all intercropped treatments. The abundance of predators and its taxa was greater only in tea plantations intercropped with C. rotundifolia or I. hendecaphylla. Of the herbivores, the abundance of Empoasca onukii Matsuda, Sternorrhyncha, Aleyrodidae, and Pentatomidae was greater in the areas intercropped with C. rotundifolia in comparison with the control, but the abundance of Thysanoptera and Geometridae caterpillars was lower. The recorded increase in the abundance of beneficial arthropods may explain the lower abundance of Thysanoptera or Geometridae caterpillars detected in the intercropped tea plantations. Our results indicate that intercropping has the potential to enhance arthropod biodiversity, and to provide an option for sustainable pest control in tea plantations.

scholarly journals Penicillium simplicissimum NL-Z1 Induced an Imposed Effect to Promote the Leguminous Plant Growth

2021 ◽  
Vol 12 ◽  
Author(s):  
Jiayao Zhuang ◽  
Chao Liu ◽  
Xiaoxue Wang ◽  
Tongxin Xu ◽  
Hao Yang
Keyword(s):  
Plant Growth ◽  
Rock Slope ◽  
Plant Biomass ◽  
Control Treatment ◽  
Leguminous Plant ◽  
Penicillium Simplicissimum ◽  
Nodule Biomass ◽  
Underlying Mechanisms ◽  
Phosphate Solubilizing ◽  
A Minor

It is found effective for phytoremediation of the guest soil spraying method by adding microbes to promote the growth of arbor leguminous plant on a high and steep rock slope. However, its underlying mechanisms remain elusive. Here, some experiments were conducted to explore the multifunctions of Penicillium simplicissimum NL-Z1 on rock weathering, nodule growth, and beneficial microbial regulation. The results show that P. simplicissimum NL-Z1 significantly increased the release of phosphorus, potassium, calcium, and magnesium from the rock by 226, 29, 24, and 95%, respectively, compared with that of the control. A significant increase of 153% in Indigofera pseudotinctoria Matsum nodule biomass, accompanied by an increase of 37% in the leguminous plant biomass was observed in the P. simplicissimum NL-Z1 treatment than in the control treatment. Interestingly, even though P. simplicissimum NL-Z1 itself became a minor microbial community in the soil, it induced a significant increase in Mortierella, which, as a beneficial microbe, can promote phosphate-solubilizing and plant growth. The results suggest that P. simplicissimum NL-Z1 could induce an imposed effect to promote leguminous plant growth, which may be conducive to the development of the phytoremediation technique for high and steep rock slope. The study provides a novel thought of using the indirect effect of microbes, i.e., promoting other beneficial microbes, to improve soil environment.

scholarly journals IRRIGATION FREQUENCIES FOR Eucalyptus grandis SEEDLINGS

2020 ◽  
Vol 28 ◽  
pp. 364-374
Author(s):  
Gustavo Henrique Miguel da Cruz ◽  
Fernando França da Cunha ◽  
Epitácio José de Souza ◽  
Andrisley Joaquim da Silva ◽  
Roberto Filgueiras
Keyword(s):  
Seed Quality ◽  
Block Design ◽  
Irrigation Management ◽  
Eucalyptus Grandis ◽  
Volume Ratio ◽  
Crop Coefficient ◽  
Experimental Period ◽  
Dry Mass ◽  
Irrigation Depth ◽  
Total Seed

One of the bottlenecks in relation to the production of forest seedlings is irrigation, especially in less-tech nurseries. The small volumes of substrate, where the seedlings develop, lead to low water storage. This fact can lead to water deficit and significant losses in the production of seedlings, generating even mortality. The objective of this study was to determine the best irrigation frequencies for Eucalyptus grandis seedling production in less-tech nurseries. The experiment was conducted between 2013/08/04 and 2013/23/07 (106 days) and conducted in Chapadão do Sul county, Brazil. The experiment was set up in a randomized complete block design, with five replications. Four irrigation frequencies were tested: IF1 (one daily irrigation - 11:00 a.m.), IF2 (two daily irrigations - 11:00 a.m. and 7:00 p.m.), IF3 (three daily irrigations - 07:00 a.m., 11:00 a.m. and 7:00 p.m.) and IF4 (four daily irrigations - 07:00 a.m., 11:00 a.m., 3:00 p.m. and 7:00 p.m.). The sample units were composed of eight seedlings in 50 cm3 conical tubes filled with soil and vermiculite in a volume ratio of 1:1. The irrigation depth was estimated by reference evapotranspiration (Penman-Monteith) multiplied by a crop coefficient equal to two. Plant height, number of definitive leaves, shoot dry mass (root and total), seed quality index, survival and efficiency of water use by eucalyptus seedlings were evaluated. The average daily irrigation depth in the experimental period was 5.2 mm. Based on the results, it is recommended for eucalyptus seedling producers, in less-tech nursery, irrigation management twice per days. (11:00 a.m. and 7:00 p.m.).

scholarly journals Tolerance to Pre-Harvest Sprouting in Lithuanian Winter Wheat Advanced Lines

2009 ◽  
Vol 63 (1-2) ◽  
pp. 45-50
Author(s):  
Žilvinas Liatukas ◽  
Vytautas Ruzgas
Keyword(s):  
Plant Growth ◽  
Winter Wheat ◽  
Filter Paper ◽  
Experimental Period ◽  
Growth Chamber ◽  
Breeding Lines ◽  
Cumulative Index ◽  
Resistant Lines ◽  
Final Score ◽  
Plant Growth Chamber

Tolerance to Pre-Harvest Sprouting in Lithuanian Winter Wheat Advanced Lines Tolerance to pre-harvest sprouting of winter wheat advanced breeding lines was evaluated at the Lithuanian Institute of Agriculture in 2005 and 2006. The tests were conducted with intact ears germinated in plastic boxes on wet filter paper in a plant growth chamber. A total of 131 breeding lines were tested during the experimental period. The experiment revealed that sprouting cumulative index (SCI) characterises resistance of lines to pre-harvest sprouting more precisely than sprouting final score (SFS). The SFS ranged from 4.3 to 9.0 in 2005 and from 5.4 to 9.0 in 2006. The SCI value was 0.14-1.0 in both years. Lines in 2005 were more susceptible to pre-harvest sprouting than those in 2006. The most resistant were found to be the lines Flair/Asketis, Torfrida/Beaver//Tarso, Širvinta1/LIA3480, while the most susceptible ones were Elena/Flair, Mermaid/Alidos, Flair/Lut.96-3 in 2005. In 2006, the most resistant lines were Pegassos/Dream, Belisar/Briz, Lars/Lut.96-3 and the most susceptible were Rostovchanka/Lut.96-3, Rector/Briz, Rostovchanka/Flair. The SFS of resistant lines was up to score 6 and the SCI value reached 0.3 in both years. The SFS of susceptible lines was 9.0 and the SCI value more than 0.9 in both years.

Triadica sebifera (Chinese tallow tree).

2021 ◽  
Author(s):  
Julissa Rojas-Sandoval
Keyword(s):  
Nutrient Recycling ◽  
Seed Kernel ◽  
Root Bark ◽  
Chinese Tallow Tree ◽  
Triadica Sebifera ◽  
Drying Oil ◽  
Vegetable Tallow ◽  
Tea Plantations ◽  
Timber Tree ◽  
A Minor

Abstract Triadica sebifera is a valuable multipurpose agroforestry species in the central Himalayan region and across Asia, and is also a popular ornamental tree for its colourful autumn leaves. The fruit of T. sebifera contains two types of fat. The white, fleshy outer seedcoat (sarcotesta) produces a fat known as Chinese vegetable tallow, while the cotyledons of the seed (kernel) yield a drying oil called stillingia oil. These oils are used as a substitute for cocoa butter in the food industry, to make paints, varnishes, soaps and candles, and to waterproof umbrellas. The leaves contain a dye, used in Asia to dye silk black. As an agroforestry species, Triadica sebifera is a good soil binder and contributes to nutrient recycling. It is planted in tea plantations as a shade tree and is also a minor timber tree. Its wood is sometimes used to make various implements, toys, furniture and Chinese printing blocks. The root, bark and leaves are used in traditional medicine in China (PROSEA, 2018; PROTA, 2018).

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