Red Beaut Research Articles

Performance of Some Japanese Plum (Prunus salicina) Cultivars in Mid-hill Condition of Kullu Valley, Himachal Pradesh

A study was conducted during February to July, 2020 and 2021 at the Horticultural Research Station Seobagh, Himachal Pradesh, India to evaluate various attributes of plum under the mid-hill temperate zone. Ten plum cultivars Red Beaut, Au Rosa, Au Amber, Satluj Purple, Kala Amritsari, Shiro, Frontier, Mariposa, Black Amber, Queen Rosa, and Angeleno grafted on wild apricot were evaluated alongside with numerous standards in a high-density experimental orchard, and these types were compared with the “Santa Rosa” variety as a control. According to the findings, Red Beaut ripened first whereas the cultivar Mariposa took 150 days from flowering to harvest, making it the last to be picked. The cv. Au Rosa had the largest trunk girth (44 cm), cv. Mariposa likewise had the longest shoots, measuring 180 cm, cv. Frontier had the highest fruit output per tree (145 kg), closely followed by the cv. Black Amber (140 kg) which also has maximum fruit size (5.4 cm), and weight (130 g). The cv. Frontier (14.1°B) showed the highest TSS, followed by the cv. Mariposa (14.0°B), while the cv. Kala Amritsari showed the lowest TSS. The plum cultivar Kala Amritsari displayed the highest fruit acidity, at 2.3%. Due to their ability to extend the repining period from May through August, the plum cultivars Red Beaut, Frointer, Mariposa, and Black Amber were found to be appropriate for commercial cultivation in Himachal Pradesh.

Nutritional Quality and Yield Performance of Plum (Prunus domestica) Varieties Grown in Punjab, Pakistan

Pakistan is ranked 17th in the world for plum production, with a total output of 67,000 tonnes. In terms of area and production, plum (Prunus domestica) is Pakistan's second largest stone fruit, after peach. Plum (Prunus domestica L.) is a temperate zone fruit crop, made up of different varieties. This study was carried out to evaluate the nutritional quality and yield performance of five different plum varieties (Methley, Shakar Prune, Santa Rosa, Hersminar, and Red Beaut) grown in the Punjab province of Pakistan. Plum samples were collected from the Horticultural Research Station, Nowshera (Soon Valley), Pakistan during May 2021 and analyzed for fruit yield and nutritional quality parameters. The maximum fruit fresh weight (52.9g) was recorded in Red Beaut and the lowest fresh weight (12.4 g) in Methley. The cultivar with the highest nutritional value was Shakar Prune with 16.4% of total soluble solids (TSS) and 12.2% of total sugars content, whereas the lowest nutritional value was recorded in Herisminar with total soluble solids (TSS) and total sugars content of 14.8% and 10.0%, respectively. All varieties showed significant variation in terms of fresh weight, total soluble solids (TSS), and total sugars. The results showed the yield performance and nutritional quality of different plum varieties, with Red Beaut and Shakarprune cultivars highlighted as the best. The study concluded that yield performance and nutritional quality depend strongly on the respective plum variety.

Improved soil physico-chemical characteristics, soil moisture and plant growth properties through vertical mulching in a plum orchard

ABSTRACTThis study investigated effects of vertical mulching with organic manures (applied into vertical holes in the soil) in combination with grass mulching of the soil surface, on plant growth, leaf and soil properties in plums (Prunus salicina Lindl. cv. Red Beaut) grown in Himachal Pradesh, India. Five manures were used for vertical mulching (farmyard manure, vermicompost, mushroom compost, ghanjeevamrit and jeevamrit) in combination with two levels of grass mulching (with and without). Vertical mulching treatments with ghanjeevamrit and vermicompost resulted in significant improvements of plant growth, leaf chlorophyll and photosynthetic rate. Leaf and soil nutrient concentrations were also highest in treatments with vermicompost and ghanjeevamrit, with the highest soil nutrient concentrations recorded when these manures were applied with grass mulching. For most plant growth parameters, trees grown with grass mulching performed better than those grown without. Soil physical properties were significantly enhanced by vertical mulching with vermicompost and ghanjeevamrit. Soil moisture at 15 and 30 cm depth was not affected by the vertical mulching with manures, but at 45 and 60 cm depth the manures had significant effects. Grass mulching was also found to be important for regulating soil moisture. The results showed the potential benefits of vertical mulching with manures in combination with grass mulching, with positive effects on both plant growth and soil fertility. The importance of grass mulching was highlighted in terms of its potential for preserving soil moisture and the use of ghanjeevamrit and vermicompost for their potential as nutrient sources and to improve soil fertility.

Plum Ripeness Analysis in Real Environments Using Deep Learning with Convolutional Neural Networks

Digitization and technological transformation in agriculture is no longer something of the future, but of the present. Many crops are being managed by using sophisticated sensors that allow farmers to know the status of their crops at all times. This modernization of crops also allows for better quality harvests as well as significant cost savings. In this study, we present a tool based on Deep Learning that allows us to analyse different varieties of plums using image analysis to identify the variety and its ripeness status. The novelty of the system is the conditions in which the designed algorithm can work. An uncontrolled photographic acquisition method has been implemented. The user can take a photograph with any device, smartphone, camera, etc., directly in the field, regardless of light conditions, focus, etc. The robustness of the system presented allows us to differentiate, with 92.83% effectiveness, three varieties of plums through images taken directly in the field and values above 94% when the ripening stage of each variety is analyzed independently. We have worked with three varieties of plums, Red Beaut, Black Diamond and Angeleno, with different ripening cycles. This has allowed us to obtain a robust classification system that will allow users to differentiate between these varieties and subsequently determine the ripening stage of the particular variety.

Evaluation of Soil Water Content Measurements with Capacitance Probes to Support Irrigation Scheduling in a “Red Beaut” Japanese Plum Orchard

Advances in electromagnetic sensor technologies in recent years have made automated irrigation scheduling a reality through the use of state-of-the-art soil moisture sensing devices. However, correct sensor positioning and interpretation of the measurements are key to the successful implementation of these management systems. The aim of this study is to establish guidelines for soil moisture sensor placement to support irrigation scheduling, taking into account the physiological response of the plant. The experimental work was carried out in Vegas Bajas del Guadiana (Extremadura, Spain) on a drip-irrigated experimental orchard of the early-maturing Japanese plum cultivar “Red Beaut”. Two irrigation treatments were established: control and drying. The control treatment was scheduled to cover crop water needs. In the drying treatment, the fruit trees were irrigated as in control, except in certain periods (preharvest and postharvest) in which irrigation was suspended (drying cycles). Over 3 years (2015–2017), a series of plant parameters were analyzed in relation to the measurements provided by a battery of frequency domain reflectometry probes installed in different positions with respect to tree and dripper: midday stem water potential (Ψstem), sap flow, leaf stomatal conductance, net leaf photosynthesis and daily fraction of intercepted photosynthetically active radiation. After making a comparison of these measurements as indicators of plant water status, Ψstem was found to be the physiological parameter that detected water stress earliest. The drying cycles were very useful to select the probe positions that provided the best information for irrigation management and to establish a threshold in the different phases of the crop below which detrimental effects could be caused to the crop. With respect to the probes located closest to the drippers, a drop in the relative soil water content (RSWC) below 0.2 would not be advisable for “non-stress” scheduling in the preharvest period. When no deficit irrigation strategies are applied in the postharvest period, the criteria are similar to those of preharvest. However, the probes located between the dripper at 0.15 and 0.30 m depth provide information on moderate water stress if the RSWC values falls below 0.2. The severe tree water stress was detected below 0.1 RSWC in probes located at 60 cm depth from this same position.

Effect of different weed management practices on growth, yield and fruit quality of plum (<em>Prunus salicina</em>) cv. Red Beaut

Effect of different weed management practices on growth, yield and fruit quality of plum (<em>Prunus salicina</em>) cv. Red Beaut

Effect of different weed management practices on soil properties and soil and leaf nutrient content of plum (Prunus salicina L) cv Red Beaut

Effect of different weed management practices on soil properties and soil and leaf nutrient content of plum (Prunus salicina L) cv Red Beaut

Using Soil Moisture Sensors for Automated Irrigation Scheduling in a Plum Crop

The growing scarcity and competition for water resources requires the urgent implementation of measures to ensure their rational use. Farmers need affordable irrigation tools that allow them to take advantage of scientific know-how to improve water use efficiency in their common irrigation practices. The aim of this study is to test under field conditions, and adjust where required, an automated irrigation system that allows the establishment of regulated deficit irrigation (RDI) strategies in a stone fruit orchard. For this, an automated device with an algorithm which combines water-balance-based irrigation scheduling with a feedback adjustment mechanism using 15 capacitive sensors for continuous soil moisture measurement was used. The tests were carried out in 2016 and 2017 in Vegas Bajas del Guadiana (Extremadura, Spain) on an experimental plot of ‘Red Beaut’, an early-maturing Japanese plum cultivar. Three irrigation treatments were established: control, RDI and automatic. The control treatment was scheduled to cover crop water needs, a postharvest deficit irrigation (40% crop evapotranspiration (ETc)) strategy was applied in the RDI treatment, while the Automatic treatment simulated the RDI but without human intervention. After two years of testing, the automated system was able to “simulate” the irrigation scheduling programmed by a human expert without the need for human intervention.

Carbohydrate and nitrogen reserves in two cultivars of Japanese plum grown under organic and conventional management

Nitrogen and carbohydrate (soluble sugars and starch) reserves were analysed in twig samples of ‘Red Beaut’ and ‘Showtime’ Japanese plum (Prunus salicina Lindl.) cultivars cultivated in two similar experimental orchards under organic and conventional management. ‘Red Beaut’ is a vigorous cultivar while ‘Showtime’ is a middle to low vigorous cultivar. Both cultivars exhibited delayed flowering and premature defoliation under organic management. In general, there were no differences in the concentration of reserves between the two types of management for either of the two plum cultivars, and, likewise, no differences were observed between cultivars, regardless of their vigor. Additionally, reserves were also analysed in plantlets of ‘Mariana 2624’ rootstock (Prunus cerasifera Ehrh × Prunus munsoniana W. Wight & Hedrick) grown in a growth chamber that simulated conditions of spring and autumn periods and subjected to organic or mineral fertilisation. Plants subjected to organic fertilisation were smaller and defoliated earlier, but the sizes of carbohydrate and nitrogen reserves were similar to that of plants grown with mineral fertilisation.

Bud take success, growth and foliage characters of different Prunus cultivars on Myrocal and Julior clonal rootstock

The present study determined the effect of clonal rootstock of Prunus and their graft compatibility with peach, plum and apricot cultivars. Prunus scion cultivars were tongue grafted on respective Prunus clonal rootstocks in the last week of January, 2006. The study indicated that with respect to graft success, Myrocal exhibited higherbud take with apricot (66.67 %) than plums (63.89 %) with 1.15 and 1.20 stock/scion ratio, respectively. Julior exhibited higher bud take with plums (91.77 %) than peaches (86.11%) with 1.10 and 1.07 stock/scion ratio, respectively, whereas, Julior exhibited higher bud take with plum (91.77 %) than peaches (86.11 %) with 1.10 and 1.07 stock/scion ratio, respectively. Comparative studies indicate higher bud take of plum cvs Frontier (91.64 % ) and Red Beaut (91.84 %) on Julior as compared to Myrocal. Peach scion cultivars recorded more annual growth in terms of plant height (0.73 m) and plant spread (0.48 m x 0.62 m) than plum scion cultivars on Julior. Contrary to higher vigour recorded in nectarine scions compared to peach scions grafted on Julior, annual growth has been observed to be higher in peaches than in nectarines. Comparative studies indicate plant height, plant spread, trunk girth, internodal length and pruning weight of both plum cultivars to be higher on Myrocal than on Julior. With the present study, it is clear that Myrocal is more vigorous than Julior rootstock and both the rootstocks can be utilized for propagation with Prunus cultivars studied.

Effects of post-harvest deficit irrigation in ‘Red Beaut’ Japanese plum: Tree water status, vegetative growth, fruit yield, quality and economic return

In early maturing fruit crops, post-harvest is usually the preferred period to apply regulated deficit irrigation (RDI) because it offers the opportunity of reducing vegetative growth and saving water without interfering with fruit growth. There are few studies of RDI on Japanese plum, in comparison with the number available for other fruit crops. We examined the effect of RDI over the post-harvest seasons of 2009–2013 on tree water status, vegetative growth, yield, fruit quality and economic return in an adult orchard of early maturing ‘Red Beaut’ Japanese plum. All treatments received the same pre-harvest irrigation of 100% of crop evapotranspiration (ETc) and post-harvest irrigation treatments were: irrigated at 100% of ETc (Control); applying 60% of water in Control (RDI-60); and applying 30% of water in Control (RDI-30). The average annual irrigation water applied to Control was 639mm. Maximum annual water savings with respect to Control were 39% for RDI-60 and 70% for RDI-30. Intercepted photosynthetically active radiation at solar noon displayed a similar pattern throughout the years with no significant differences between irrigation treatments in any year. However, the RDI treatments were suitable for reducing total pruning weight. Fruit yield in RDI-30 was similar to Control for each of the five years following deficit irrigation. In the long-term (five seasons), the effect of post-harvest RDI had no negative cumulative effect on tree productivity. Therefore, for early maturing Japanese plum it can be concluded that allowing a progressive post-harvest water stress that limits the decline in Ψstem to values of −1.65MPa in early August, with a maximum decrease of 0.014MPaday−1, corresponding in this study to RDI-30, appears not only to be an effective way of saving water, but also acts as a useful tool to control vegetative growth (considered as total pruning), maintain fruit yield and quality and increase grower's final return.

Chemical, functional and quality properties of Japanese plum ( Prunus salicina Lindl.) as affected by mulching

The aim of this study was to contribute to the chemical, functional and qualitative characterisation of Japanese plum ( Prunus salicina L., cv. Red Beaut, genotype “606”) cultivated with and without a mulching plastic by investigating the organic acids and sugars profiles, the total antioxidant activity and total polyphenols content, the volatile composition and the sensory profile. Results indicated that total sugars, organic acids contents and the total concentration of volatile compounds were slightly higher in plums from trees with the mulching plastic film being used as a cultural practice, although differences were not statistically significant. Sixteen compounds were isolated from the volatile fraction from six different chemical families: aldehydes, monoterpenes, monoterpenoids, phenylpropanoids, acids and ketones. The major compounds in the volatile profile of plum juices were trans-linalool oxide, terpinolene, nonanal and α-terpineol. However, total antioxidant activity, total polyphenols content and the sweetness intensity were decreased by the use of the mulching plastic. Therefore, mulching with plastic materials with high light reflectance (e.g. white) seemed to be required to improve the quality of plums.

Ovule development at anthesis in Japanese plum (Prunus salicina Lindl.) cultivars

The stage of ovule development at anthesis has been studied in two consecutive years in seven major cultivated plum cultivars: "Red Beaut", "Fortune", "Angeleno", "Santa Rosa", "Larry Ann", "Son Gold" and "Golden Japan". Ovules examined were in general delayed. In much of them mature embryo sacs were not found at time of anthesis. Differences among cultivars were found and these differences were consistent during both years, indicating a genetic determination. In addition, a high heterogeneity of the developmental stage of the ovules examined in each cultivar was observed. The year influenced the developmental stages of ovules at anthesis, and ovules were more delayed in 2002 than in 2003. Cultivars which showed a more advanced ovule development were those that flowered later, in spite of the fact that chilling requirements for breaking of rest were adequately fulfilled during both years. This work gives interesting information regarding the stage of ovule maturity at anthesis in Japanese plum cultivars, which is closely related to their fruit set viability.

Susceptibility of several Japanese plum cultivars to pests and diseases in a newly established organic orchard

The susceptibility of 14 Japanese plum cultivars to an aphid pest and three fungal diseases was analysed during 2007 and 2008 in two experimental orchards, one in organic and the other in conventional management. There was a significantly higher incidence of green peach aphids [ Myzus persicae (Sulzer)] for most of the cultivars in the organically managed treatment. ‘Fortune’, ‘Primetime’, ‘Larry Ann’ and ‘Sapphire’ were the cultivars most affected, and ‘Souvenir’ suffered the lowest attack in both treatments. Shot hole disease ( Wilsonomyces carpophilus) affected both orchards at low levels, and only two cultivars, ‘Santa Rosa’ and ‘Larry Ann’, suffered a moderate attack. Powdery mildew ( Sphaerotheca pannosa) incidence was significantly higher in the conventionally managed orchard and only the ‘Red Beaut’ cultivar was affected. Rust disease ( Tranzschelia spp.) incidence was significantly higher in the organic treatment. The cultivars in which the rust disease appeared earliest and reached the highest levels were ‘Showtime’, ‘Santa Rosa’, ‘Friar’, and ‘Larry Ann’. An intense rust infestation in leaves provoked a premature defoliation in the organic plot, indicating that proper control of this disease is important to maintain tree vigour and yield.

Epidemiology of sharka disease in Spain

PPV was first detected in Spain in 1984 in Japanese plum (Prunus salicinaLindl) cv. Red Beaut and spread very quickly to other Japanese and European plums and apricot cultivars but left peach cultivars unaffected. In the years following the detection of PPV, the predominant aphid species visitingPrunusorchards in Mediterranean areas wereAphis gossypiifollowed byAphis spiraecola, the latter being the main aphid species found at present. Both species are considered to be the main vectors of PPV in Spanish earlyPrunusgrowing areas. Spatial analysis of the spread of PPV‐D in Japanese plum and apricot trees confirmed the lack of significant association between immediately adjacent trees. The observed spatial pattern of sharka suggests a lack of movement of PPV‐viruliferous aphid vectors to immediately adjacent trees and indicates their preferential movement to trees several tree spaces away. PPV‐D is the only type currently present in Spain, with the exception of a PPV‐M outbreak that was detected in and successfully eradicated from Aragón in 2002. The short‐distance spread of PPV‐M infection occurred as far as 12 m along the rows of peach trees. However, PPV‐D has not been observed to spread through peach cultivars, despite being grown in the vicinity of heavily infected plots of apricot or Japanese plum trees.

Occurrence of powdery mildew ( Sphaerotheca pannosa) in Japanese plum in Northern Israel and its control

Powdery mildew, caused by the fungus Sphaerotheca pannosa (Wallr.) Lev., is a widespread and destructive disease of nectarine in the northern region of Israel. Powdery mildew has not previously been observed on Japanese plum ( Prunus salicina Lindl.) in this region, and we describe here the first occurrence of powdery mildew on plum trees in the largest growing area in Northern Israel. The first symptoms and signs were observed on 22 April 2000 as single colonies on young plum fruits, and these expanded during the season and covered large parts of the fruit. The disease caused browning and russeting of the fruit surface, and chlorotic spots on mature and coloured fruits until harvest. The disease on leaves was less severe, characterized by chlorotic (bright yellowish) lesions of 5–10 mm diameter on the upper surface and “oil spot” type lesions on the lower surface. Microscopic examinations revealed that the mycelium, conidiophores and conidia were similar to those of S. pannosa that attacks nectarine trees in this region. Cleistothecia were not found during the growing season. Disease rating in two orchards showed that fruits were more infected than leaves. The most severly affected cultivar was ‘Red Beaut’ with 27% and 97%, respectively, of leaves and fruits infected. Field experiments conducted in 2000, 2002 and 2004 showed that foliar applications of DMI (demethylation inhibitor) fungicides reduced disease development, but failed to provide satisfactory control. DMIs were less effective than the strobilurin, kresoxim-methyl and polyoxin B in controlling S. pannosa on fruits and leaves of field-grown Japanese plum trees. However, spraying of sulphur significantly enhanced the inhibitory effect against powdery mildew and provided the highest level of disease control. In the light of experience with S. pannosa in nectarine , it is suggested that intensive use may have led to reduced efficacy of the DMI fungicides in controlling S. pannosa in nectarine and plum orchards. An alternative disease management programme, which integrates early and timely applications of effective fungicides, and tank-mixtures of DMI fungicides with sulphur, may provide an improved level of powdery mildew control and could be valuable to avoid the spread of powdery mildew and to minimize the development of fungicide resistance.

Phenetic Characterization of Plum Cultivars by High Multiplex Ratio Markers: Amplified Fragment Length Polymorphisms and Inter-simple Sequence Repeats

Variability of commercial plum (Prunus L. sp.) cultivars is unknown since breeding often involves intercrossing hybrids with several species but has been based on a low number of parents. Molecular markers like amplified fragment length polymorphisms (AFLP) and inter-simple sequence repeats (ISSR), which sample multiple loci simultaneously, have become increasingly popular, and were used to characterize 24 diploid and four hexaploid cultivars of plum. Seven AFLP and six ISSR primers were used, and resulted in amplification of 379 and 270 products, respectively. Unweighted pair-group method with arithmetic averages (UPGMA) dendrograms, based on similarity coefficients, reflected a clear separation between diploid and hexaploid plums. Among diploid plums, two pairs of cultivars were relatively distinct from the rest, namely `Golden Japan' and `Methley' and `Ozark Premier' and `Songold'. Furthermore, several cultivars were grouped together both with AFLP and ISSR analysis: 1) `Ambra', `Red Beaut', and `Black Beaut', 2) `Black Diamond' and `Royal Diamond', 3) `June Rose', `Santa Rosa', and `Royal Red', and iv) `Freedom', `Larry Ann', and `Queen Rosa'. Although the phenetic classification obtained by the two methods were similar (r = 0.73, for the diploid group), ISSR had a higher reproducibility and percentage of polymorphisms (87.4% vs. 62.8%) than AFLP. Methodological aspects of both markers systems are discussed. Results obtained suggest that the AFLP and ISSR approaches are valuable tools for identification of specific genotypes and analysis of phenetic relationships in plum.

Postharvest water stress of an early maturing plum

Postharvest water stress was imposed on a May harvested plum (Primus salicina Lindl. cv. Red Beaut) over a three year period. Control trees were irrigated at approximately 100% ET. One stress treatment (Tl) received 50% of the water applied to the control. The second stress treatment (T2) was subjected to cycles of on-and-off irrigation which varied from year to year. All treatments were fully irrigated at about 100% ET through harvest. Treatment Tl received about 30 cm less irrigation water than the control and showed no decrease in yield, fruit weight or fruit quality over all three years. Treatment T2 received about the same amount of water as Tl in the first two years of the experiment and also showed no decrease in productivity. In the third year, T2 was irrigated only for a single three week period after harvest which saved over 60 cm of applied water. The trees were extensively defoliated by the end of the season, showed some shoot and scaffold dieback, and had reduced yields in the following year....

Diseases, Physiological Disorders, and Injuries of Plums Marketed in Metropolitan New York

Retail and consumer losses in nine major cultivars of western plums marketed in metropolitan New York and sampled for 15 consecutive weeks during the 1983 and 1984 seasons averaged 4.2 and 5.0%, respectively, for a total market loss of 9.2%. Specific causes were parasitic diseases (3.4%), physiological disorders (2.1%), and injuries (3.7%). Total losses were higher in the cultivars Casselman and President than in Red Beaut, Santa Rosa, Eldorado, Simka, Friar, Italian Prune, and Angelino. In a sample of three of the cultivars in 1992, total consumer losses were 4.7%, statistically unchanged from 1983-1984 levels. The principal disease in both surveys was brown rot (Monilinia spp.), which caused up to 50% of the disease losses [...]