scholarly journals Use of alpha-naphthylacetic acid in ovary thinning and preharvest fruit drop reduction in apple trees

Author(s):  
A. I. Kuzin ◽  
Yu. B. Nazarov ◽  
A. A. Shmakova ◽  
S. A. Karpukhina ◽  
A. I. Flyagin

Chemical thinning of apple ovaries in intensive orchards is highly relevant. This farming practice reduces manual labour, decreases  the  fructification  interval and improves apple quality. Growth regulators, including alpha-aphthylacetic acid,  also  reduce preharvest fruit drop allowing for an optimal harvest capacity. The research aimed to study the impact of different alpha-naphthylacetic acid application rates on ovary thinning  and preharvest  fruit drop. Assays were conducted in 2019—2020  in a  leached-chernozem experimental apple orchard of the Michurin Federal Research Centre  in Tambov Region. Assay 1 studied the treatment impact on apple tree thinning at rates 100, 200, 300 and 400 ml/ha in 8—12 mm fruits, assay 2 (treatment 2 weeks prior to expected harvest) —  on reducing preharvest apple drop at rates 200, 300 and 400 ml/ha. The treatments significantly reduced the number of ovaries in the Zhigulevskoe/62-396 cultivar and increased mean apple fruit weight. Such increase was an important yield-rising factor in the 300 and 400 ml/ha treatments. Alpha-naphthylacetic acid treatments in 8—12 mm fruits had a significant lowering impact on total leaf nitrogen content. The treatments also induced a significant reduction in preharvest apple fruit drop, with the best effect at rate 300 ml/ha. No explicit impact of alpha-naphthylacetic acid on fructification interval was observed in the study period.

Agronomy ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 540
Author(s):  
Juozas Lanauskas ◽  
Nobertas Uselis ◽  
Loreta Buskienė ◽  
Romas Mažeika ◽  
Gediminas Staugaitis ◽  
...  

The circular economy concept promotes the recycling of agricultural waste. This study was aimed at investigating the effects of cattle horn shavings on apple tree nitrogen nutrition. Ligol apple trees on P 60 rootstock were the object of the study. The experiment was conducted in the experimental orchard of the Institute of Horticulture, Lithuanian Research Centre for Agriculture and Forestry, from 2015 to 2018. Two fertiliser rates were tested: 50 and 100 kg/ha N. Horn shavings (14.1% N) were applied at the end of autumn or at the beginning of vegetation in the spring and in one treatment 100 kg/ha N rate was divided into two equal parts and applied both in autumn and spring. The effects of the horn shavings were compared with the effects of ammonium nitrate (34.4% N) and the unfertilised treatment. The lowest mineral nitrogen content was found in the unfertilised orchard soil and the soil fertilised with horn shavings in the spring at 50 kg/ha N equivalent. In all other cases, the fertilisers increased the soil’s mineral nitrogen content. The lowest leaf nitrogen content was found in apple trees that grew in the unfertilised orchard soil or soil fertilised in the spring with 50 kg/ha N of horn shavings (1.58–2.13%). In other cases, leaf nitrogen content was higher (1.77–2.17%). The apple trees with the lowest leaf nitrogen content produced the smallest average yield (34.5–36.6 t/ha). The highest yield was recorded from fruit trees fertilised with 50 kg/ha N of ammonium nitrate applied in spring or horn shavings applied in autumn (42.4 and 41.4 t/ha, respectively). The influence of horn shavings on the other studied parameters was similar to that of ammonium nitrate. Horn shavings, like nitrogen fertiliser, could facilitate nitrogen nutrition management in apple trees, especially in organic orchards, where the use of synthetic fertilisers is prohibited.


2014 ◽  
Vol 41 (8) ◽  
pp. 884 ◽  
Author(s):  
Sebastian Saa ◽  
Patrick H. Brown

Fruit presence often positively and seldom negatively affects leaf carbon assimilation rate in fruit-trees. In almond (Prunus dulcis (Mill.) DA Webb) the presence of fruit often results in the death of the fruit bearing spurs. The mechanism of this effect is unclear, but may be a consequence of diminished carbon assimilation rate in leaves adjacent to fruit and the subsequent depletion of nutrient and carbohydrates reserves. This study evaluated the influence of fruit on leaf carbon assimilation rate and leaf nitrogen throughout the season. Carbon assimilation rate (Aa), rubisco carboxylation capacity at leaf temperature (Vcmax@Tleaf), maximum rate of RubP regeneration at leaf temperature (Jmax@Tleaf), leaf nitrogen on a mass basis (N%) and area basis (Na), and specific leaf weight data were recorded. Fruit presence negatively affected leaf nitrogen concentration by a reduction in specific leaf weight and leaf nitrogen content. The impact of fruit presence on carbon assimilation rate was predominantly associated with the negative effect of fruit on Na and resulted in a significant reduction in Jmax@Tleaf and therefore in Aa, especially after full leaf and fruit expansion. The reduction in leaf area, leaf nitrogen, reduced Jmax@Tleaf and decreased carbon assimilation rate in the presence of fruit explains the negative effects of fruit presence on spur vitality.


HortScience ◽  
2001 ◽  
Vol 36 (1) ◽  
pp. 45-48 ◽  
Author(s):  
Daniel L. Ward ◽  
Richard P. Marini ◽  
Ross E. Byers

Preharvest fruit drop of apple [Malu×domestica (L.) Borkh.] can cause significant crop losses, but factors controlling date of individual fruit drop are unknown. In three types of experiments, we investigated the relationships among seed number/fruit, fruit weight, and day of year of drop. By shading in mid-May and stigma excision before bloom, we induced variability in seed number. Dropped fruit were weighed, and their seeds were counted daily from late August until all fruit had dropped. Nontreated trees were studied similarly. Regression analyses were used to assess relationships among day of drop, fruit weight, and seed number/fruit. Substantial variation in day of drop of individual fruit was not explained by seed number of the fruit in these experiments with `Smoothee Golden Delicious', `Redchief Delicious', and `Commander York'.


2021 ◽  
Vol 13 (2) ◽  
pp. 52-62
Author(s):  
Azad A. Mayi ◽  
Naji Isam Barwary ◽  
Hasan Salim Nabi

This research was conducted on pomegranate transplants in a lath house during the growth season of 2020 of college of Agricultural engineering science, university of Duhok, to investigate the impact of spraying of Prosopis Farcta, Urtica Dioica and Disper root with 0,100, and 200 mg.L-1 concentration, with 0,100, and 200 mg.L-1 concentration and with (0, 75, and 150 mg.L-1) concentration respectively, on vegetative growth, nutrients contents of pomegranate transplants. The collected data indicate that the spraying of Prosopis Farcta extract, Urtica Dioica and Disper root especially at 200, 200, and 150 mg.L-1 respectively resulting in a considerable increase in the majority of the examined parameters. At high concentrations, the interaction of three examined components resulted in the maximum values of branches number 14.57, transplant height 143.67 cm, leaves number 157.33, Chlorophyll 48.97, Roots number 10, Root length 42.67 cm, leaf nitrogen content 2.507 %, phosphorus 0.267 % and potassium 1.433 %.


Author(s):  
Neha Sinha ◽  
Mahendra Pal ◽  
Vinod Kumar ◽  
Anita Chaudhary ◽  
Ankit Singh Bhadauria

A field experiment was conducted to study the impact of temperature and relative humidity on fruiting behaviour and fruit quality of different mango varieties in Central Plain Zone of Uttar Pradesh during the fruiting year 2017-18 in the Garden of the Department of Horticulture, C.S. Azad University of Agriculture and Technology, Kanpur. The experiment was laid out in Randomized Block Design with 3 replications. Seven varieties of mango were taken for study. Fruiting attributes as influenced by temperature and relative humidity differed significantly in different varieties. Chausa taken highest number of days followed by Amrapali, while Dasheri and Gaurjeet recorded earliest fruit setting. The maximum marble size fruit was noted in Chausa while maximum mature fruit was noted in Local. The maximum fruit drop was recorded under Chausa followed by Dasheri, whereas minimum fruit drop was recorded under Local. Gaurjeet mature first (24th May) followed by Bombay Green (25th May) and Husnara (30th May). Chausa (26th June) and Amrapali (10th July) mature late and very late respectively. The maximum fruit length and width was found in Chausa among all of the varieties followed by Dasheri in length and Husnara in width. The maximum weight of fruit, fruit pulp, stone and peel was recorded in Chausa followed by Husnara (except peel weight), while, the maximum pulp % was recorded in Amrapali. The variety Gaurjeet and Bombey Green both mature first (71 days) followed by Husnara (75 days) while, Amrapali taken longest duration (124 days) followed by Chausa (109 days) and Local (104 days). It has been observed that during fruit setting and fruit development and maturity mango requires less RH as compared to panicle initiation. During growth and maturity RH positively correlated like temperature in all the varieties. It is concluded that mango variety Chausa being maximum in fruit weight, fruit pulp, stone and peel and medium maturing may found suitable for this region.


2020 ◽  
Vol 7 (04) ◽  
Author(s):  
A B Priyanshu ◽  
M K Singh ◽  
Mukesh Kumar ◽  
Vipin Kumar ◽  
Sunil Malik ◽  
...  

An experiment was conducted at Horticultural Research Centre, SVP University of Agriculture and Technology, Meerut (UP) during Rabi season of 2018-19 to assess the impact of different INM doses on yield and quality parameters of garlic. A total of ten treatments consisting of combinations of inorganic fertilizers, organic fertilizers and bio-fertilizers like T1- (Control), T2RDF (100:50:50 kg NPK ha-1), T3-RDF + 20 kg sulphur + FYM 20 ton ha-1, T4- RDF + 20 kg sulphur + VC 4 ton ha-1, T5- 75% RDF + 40 kg sulphur + 5 ton FYM ha-1+ PSB 5 kg ha-1, T6-75% RDF + 40 kg sulphur + 2 ton VC + Azotobacter 5 kg ha-1, T7- 75% RDF + 40 kg sulphur + FYM 3 ton + VC 1 ton+ PSB 5 kg + Azotobacter 5kg ha-1, T8- 50% RDF + 40 kg sulphur + FYM 5 ton + VC2 ton + PSB 5 kg ha-1, T9- 50% RDF + 40 kg sulphur + FYM5 ton + VC 2 ton+ Azotobacter 5 kg ha-1and T10- 50% RDF + 40 kg sulphur + FYM 5 ton + VC2 ton + PSB 5 kg + Azotobacter 5 kg ha-1 were used in Randomized Block Design and replicated thrice. Out of these an application of T7 (75% RDF + 40 kg sulphur + FYM3 ton + VC 1 ton ha-1 + PSB 5 kg + Azotobacter 5 kg ha-1) was found to be significantly superior in term of yield and attributing parameters of garlic.


2021 ◽  
Vol 13 (4) ◽  
pp. 739
Author(s):  
Jiale Jiang ◽  
Jie Zhu ◽  
Xue Wang ◽  
Tao Cheng ◽  
Yongchao Tian ◽  
...  

Real-time and accurate monitoring of nitrogen content in crops is crucial for precision agriculture. Proximal sensing is the most common technique for monitoring crop traits, but it is often influenced by soil background and shadow effects. However, few studies have investigated the classification of different components of crop canopy, and the performance of spectral and textural indices from different components on estimating leaf nitrogen content (LNC) of wheat remains unexplored. This study aims to investigate a new feature extracted from near-ground hyperspectral imaging data to estimate precisely the LNC of wheat. In field experiments conducted over two years, we collected hyperspectral images at different rates of nitrogen and planting densities for several varieties of wheat throughout the growing season. We used traditional methods of classification (one unsupervised and one supervised method), spectral analysis (SA), textural analysis (TA), and integrated spectral and textural analysis (S-TA) to classify the images obtained as those of soil, panicles, sunlit leaves (SL), and shadowed leaves (SHL). The results show that the S-TA can provide a reasonable compromise between accuracy and efficiency (overall accuracy = 97.8%, Kappa coefficient = 0.971, and run time = 14 min), so the comparative results from S-TA were used to generate four target objects: the whole image (WI), all leaves (AL), SL, and SHL. Then, those objects were used to determine the relationships between the LNC and three types of indices: spectral indices (SIs), textural indices (TIs), and spectral and textural indices (STIs). All AL-derived indices achieved more stable relationships with the LNC than the WI-, SL-, and SHL-derived indices, and the AL-derived STI was the best index for estimating the LNC in terms of both calibration (Rc2 = 0.78, relative root mean-squared error (RRMSEc) = 13.5%) and validation (Rv2 = 0.83, RRMSEv = 10.9%). It suggests that extracting the spectral and textural features of all leaves from near-ground hyperspectral images can precisely estimate the LNC of wheat throughout the growing season. The workflow is promising for the LNC estimation of other crops and could be helpful for precision agriculture.


2021 ◽  
Vol 28 (1) ◽  
pp. 42-50
Author(s):  
Nicole M. Glenn ◽  
Lisa Allen Scott ◽  
Teree Hokanson ◽  
Karla Gustafson ◽  
Melissa A. Stoops ◽  
...  

Financial well-being describes when people feel able to meet their financial obligations, feel financially secure and are able to make choices that benefit their quality of life. Financial strain occurs when people are unable to pay their bills, feel stressed about money and experience negative impacts on their quality of life and health. In the face of the global economic repercussions of the COVID-19 pandemic, community-led approaches are required to address the setting-specific needs of residents and reduce the adverse impacts of widespread financial strain. To encourage evidence-informed best practices, a provincial health authority and community-engaged research centre collaborated to conduct a rapid review. We augmented the rapid review with an environmental scan and interviews. Our data focused on Western Canada and was collected prior to the pandemic (May–September 2019). We identified eight categories of community-led strategies to promote financial well-being: systems navigation and access; financial literacy and skills; emergency financial assistance; asset building; events and attractions; employment and educational support; transportation; and housing. We noted significant gaps in the evidence, including methodological limitations of the included studies (e.g. generalisability, small sample size), a lack of reporting on the mechanisms leading to the outcomes and evaluation of long-term impacts, sparse practice-based data on evaluation methods and outcomes, and limited intervention details in the published literature. Critically, few of the included interventions specifically targeted financial strain and/or well-being. We discuss the implications of these gaps in addition to possibilities and priorities for future research and practice. We also consider the results in relation to the COVID-19 pandemic and its economic consequences.


2017 ◽  
Vol 45 (1) ◽  
pp. 120-125 ◽  
Author(s):  
Ersin ATAY ◽  
Seckin GARGIN ◽  
Ahmet ESITKEN ◽  
N. Pinar GUZEL ◽  
A. Nilgun ATAY ◽  
...  

Orchard performance is influenced by weed competition. In this study, the effects of weed competition on nutrient contents, chemical and physical fruit quality properties were sought. The study was carried out in a high-density apple orchard (‘Golden Delicious’/M.9) over two consecutive growing seasons. The effect of weed competition was studied at three different levels: weak, moderate and strong. Fruit firmness, soluble solids content, macronutrients (such as nitrogen, potassium and calcium) and potassium+magnesium/calcium ratio in fruit were significantly affected by weed competition. Strong weed competition negatively affected soluble solids content and potassium+magnesium/calcium ratio. In both trial years, soluble solids content was significantly higher in weak weed competition. In the first year of the study, soluble solids content ranged between 13.77±0.06% (strong weed competition) and 15.20±0.10% (weak weed competition). In the following year, soluble solids content values were determined as 13.13±0.23% in strong weed competition and 13.83±0.21% in weak weed competition. Weak weed competition showed superiority for fruit weight and potassium+magnesium/calcium ratio. As a whole, this study indicates that insufficient weed control in tree rows might be a limiting factor for fruit quality in high-density apple orchards.


1996 ◽  
Vol 11 (1) ◽  
pp. 39-47 ◽  
Author(s):  
M. Sean Clark ◽  
Stuart H. Gage

AbstractWe evaluated the effects of free-range chickens and geese on insect pests and weeds in an experimental, nonchemical agroecosystem consisting of an apple orchard with intercropped potatoes. The objective was to assess the potential of these domestic bird species as biological control agents. Four insect pests were studied: plum curculio, apple maggot, Japanese beetle, and Colorado potato beetle. Chickens fed on several potential crop pests, including Japanese beetle. Although Japanese beetles were less abundant on apple trees when chickens were present, the proportion of damaged fruit was not reduced. Furthermore, chickens did not affect weed abundance or crop productivity. In contrast, geese were effective weeders. Their activities reduced weed abundance and increased potato plant growth and yields compared with a minimally weeded control. In addition, the activities of geese indirectly reduced apple fruit damage by plum curculio and increased the proportion of pest-free fruit, possibly because removal of vegetation by the geese reduced humidity at the soil surface and therefore reduced the activity of plum curculio.


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