Guava Genotypes Research Articles

Studies on Physical Attributes of Guava (Psidium guajava L.) Genotypes in Awadh Region

Guava (Psidium guajava L.), a prominent fruit in tropical and subtropical regions, exhibits significant variability in physical attributes across different genotypes. This study aimed to evaluate the physical characteristics of eight guava genotypes (Lalit, Shweta, CISHG-1, CISHG-31, Allahabad Safeda, L-49, Taiwan, and VNR Bihi) in the Awadh region. The attributes assessed included fruit length, breadth, weight, volume, and specific gravity. Results indicated substantial variations among the genotypes. The longest fruits were observed in Taiwan (9.88 cm), while Shweta had the shortest (6.17 cm). Taiwan also exhibited the greatest breadth (9.29 cm) and weight (465 g), whereas L-49 had the smallest breadth (6.24 cm) and weight (141 g). Fruit volume ranged from 139 ml in L-49 to 462 ml in Taiwan. Specific gravity varied from 1.005% in VNR Bihi to 1.030% in Shweta, indicating differences in fruit density. These findings highlight the genetic diversity among guava genotypes and underscore the potential for selecting specific genotypes based on desired physical attributes for cultivation and market preferences. This study provides valuable insights into guava breeding programs aimed at improving fruit quality and marketability.

Physical and chemical characterization of guava (Psidium guajava L.) genotypes grown in subtropical condition

Guava is a high-value tropical fruit that is widely grown in tropical and subtropical regions around the world. In the adaptation studies carried out in Turkey, guava was determined as the most prominent species with its cold resistance feature. The use of seedlings in cultivation created a genetic variation and differences were observed between the resulting genotypes, especially in terms of fruit size, shape and colour. Based on this observation, this study aimed to characterize 13 different guava fruit genotypes based on physical, chemical, bioactive and aroma properties. In the adaptation studies carried out in Turkey, guava was determined as the most prominent species with its cold resistance feature. There is only one commercial variety namely ‘Ruby Supreme’ grown in Turkey. Presently, the interest of the guava cultivation has been increased and farmers were used seedling material instead of vegetative to establish orchard. Due to the cross pollination, it has been observed great variation in the population. Therefore, it is important to select promising genotypes according to fruit size, shape and colour. The present study was evaluated 13 different guava genotypes according to physical, chemical, bioactive and aroma properties. Significant differences were observed among the genotypes. One genotype was found superior over all the genotypes, in terms of fruit weight (131.44 g) and length (82.00 mm). Although three genotypes were having lower values than the other samples in results of total soluble solids, they had higher results in terms of antioxidant capacity and total phenolic content. Two genotypes formed a separate group from all other genotypes in terms of (Z)-3-Hexen-1-yl acetate (sweet, pear, melon), 3-Hexenal (melon, tropical) and Ethyl alcohol (fruit and sweet) components. The flavor components are distinctive for the guava samples, as are the physical properties. It was also determined that the white guava genotypes had very different chemical and aromatic properties from other genotypes. The promising genotypes can be utilized in the future breeding programme to improve new guava varieties.

Genetic diversity and stability analysis of the improved cultivars of guava and their related species

Guava (Psidium guajava L.) is an important fruit crop in the tropical and sub-tropical world. The morphological, biochemical, and molecular (using 56 microsatellite markers) characterization was carried out on 18 guava genotypes and related species (P. guineense) during 2018–2022. The present study exhibited a wider range of variability: fruit weight (61.5–68.4 g); fruit diameter (4.20–7.91 cm); total soluble solids (8.50–13.40 °Brix); titrable acidity (0.20–0.64%); reducing sugar (2.55–7.00 mg glucose /g); ascorbic acid (76.4–196.3 mg/100 g); total phenol (125.9–305.4 mg GAE/100 g pulp); and total flavonoid content (172.30–948.5 mg QE/100 g pulp). The antioxidant activities (FRAP and DPPH) showed a favorable relationship with ascorbic acid, total phenol, total flavonoid, and total flavonol content. Red-fleshed genotypes were found superior for all the quality parameters over white-fleshed genotypes. The molecular analysis generated 213 alleles from 56 markers, with 2–9 alleles per locus (mean = 3.80). Apart from the genetic diversity, the improved cultivars were also distinguished by a set of markers: RCGH-4 (mPGCIR-184 and mPGCIR-194); RCGH-1 (mPGCIR-108 and mPGCIR-243); RCG-11 (mPGCIR-206 and mPGCIR-325); and RCGH-7 (mPGCIR-16 and mPGCIR-19). The cluster analysis indicated that P. guineense was the most diverse of the cultivated species, and all the red flesh genotypes were close to each other. Furthermore, RCG-11 had a lower seed content (58.89 per 100 g pulp), while RCGH-1 and RCGH-4 were stable for fruit weight and seed number, which can be promoted for commercial production and future crop improvement programs.

Estimating the Morphological Variability of Guava (Psidium guajava L.) Genotypes in Jabalpur District, India

As variability is crucial for crop improvement, it is better to characterise several genotypes that are derived from either seedlings or wild types. This research facilitates the identification of cultivars, genotypes and the elimination of identical plants within populations. The study was conducted in year 2022-23 with thirty-three guava genotypes of Jabalpur district to examine various morphological characteristics such as tree height, trunk girth and canopy diameter, branching attitude, stem colour in young shoots, branching density, mature leaf colour, leaf shape, leaf base shape, leaf tip shape, leaf curvature and leaf twisting. The experimental investigation was carried out at the Fruit Research Station, Imaliya, under the Department of Horticulture at the College of Agriculture, Jabalpur, Madhya Pradesh. Genotypes exhibited notable diversity in their morphological traits with respect to height, gith, canopy and several leaf-based characteristics. For the estimation of diversity, the DUS guideline of UPOV was followed. All the genotypes in this study aged between eight to thirteen years. Descriptive statistics showed that, the height of the trees varied between 2.78m (JG-322) and 6.12m (JG-325). The trunk girth ranged between 27.21cm (JG-314) to 87.23cm (JG-319). The canopy in the east-west direction ranged from 4m (JG-325) to 8.34m (JG-322) whereas, in north-south direction varied 3.68m (JG-325) to 8.41m (JG-322). The observed diversity in these traits yielded significant insights that might drive the selection of parental plants for an advanced guava breeding initiative.

Studies on flowering behavior in guava genotypes of Jabalpur region

Studies on flowering behavior in guava genotypes of Jabalpur region

Evaluation of bioactive compounds, antioxidant capacity and mineral elements in the leaves of guava (Psidium guajava L.) genotypes from China

Guava (Psidium guajava L.) is a medicinal tree species and its leaves are rich in beneficial bioactive compounds with antioxidant capacity. China has the second-largest planting area in the world however a comprehensive evaluation of the antioxidant capacity of guava genotypes in China has not yet been conducted yet. To identify the desirable genotypes with the greatest antioxidant capacity, 18 guava genotypes widely cultivated in China were collected in a germplasm garden. In this study, the antioxidant capacity, bioactive compound contents and mineral element contents of guava leaves were assessed. Genotypic variation was observed for antioxidant capacity, bioactive compound contents and mineral element contents in guava leaves. The bioactive compound contents were all significantly and positively correlated with the antioxidant capacity in guava leaves. Correlation analysis indicated that the total phenolic total triterpenoid contents were significantly related to the total phosphorus content. Principal component analysis and cluster analysis showed that DW was superior in antioxidant capacity (radical scavenging abilities of DPPH and ABTS) and total phenolic, total flavonoid and total triterpenoid contents, and the medicinal quality of superior guava genotypes was regulated by the leaf mineral element contents, especially phosphorus. This study is not only helpful for developing guava genotypes with superior medicinal quality in the future but can also provide theoretical support for fertilization management in the cultivation of superior guava genotypes to achieve higher medicinal quality.

Genetic diversity analysis of guava (Psidium guajava L) genotypes in West Bengal, India

A total 28 traits enabled an assessment of the genetic variability of twenty-four guava genotypes. Many of these traits are significantly important and used for improvement programmes regarding fruit quality and yield. The TSS of fruit ranged from 8.57 0B (China genotype) to12.19 0B (Arka Kiran) and seed number/fruit 109.58 (Taiwan) to 303.67 (China genotype). Correlation studies revealed a strong positive correlation among quantitative traits related to fruit yield and quality while negative correlation between qualitative traits. Principal component analysis showed that the first three components with Eigen values could explain more than 76.99% of the total variation. PC1, PC2 and PC3 accounted for 41.15, 24.74 and 11.10%, respectively. Cluster analysis distinguished all the genotypes into three clusters/groups. The PCA and clustering analysis indicated a higher level of diversity in guava genotypes. Local cultivars such as Baruipur Local, Khaja, and Mohammad Khaja genotypes, as well as improved cultivars such as Arka Kiran, Philippines genotypes, were identified as having desirable fruit quality traits that could be used for commercialization and crop improvement.

Response of guava (Psidium guajava) genotypes to air-layering under sub-humid southern Rajasthan

Response of guava (Psidium guajava) genotypes to air-layering under sub-humid southern Rajasthan

Morphological Characterization of Guava Genotypes Based on Leaf and Fruit Parameters under Mid-hill Conditions of Nepal

Guava (Psidium guajava L.) popularly known as poor man's apple is one of the common fruit crops cultivated in terai, inner terai and hilly areas of Nepal. There are numerous genotypes available within the country but absence of their proper characterization is impeding guava improvement program The present study was carried out with six guava genotypes (Apple guava, Bangalore, pear shaped, KG-1, Illam Selection and Bari) to investigate morphological characters viz leaf qualitative and fruit qualitative and quantitative characters. The single factor experiment was carried out in randomized complete block design with four replications at National Horticulture Research Centre farm, Khumaltar in the year 2019 and 2020 Four plants of each genotypes were studied which were planted in the year 2015. Four mature leaves and fruits were randomly collected for qualitative characterization and all marketable fruits were collected for the study under mid hill conditions. Among them Apple Guava and KG-1 were found promising due to its attractive fruit shape and size as well as preferable taste and aroma. While observing the fruit qualitative characters maximum fruit length was found in Pear Shaped (71.1 mm) and the minimum was found in Bari (50.2 mm). Similarly, the highest individual fruit weight was observed in Apple Guava (229.5 gm) and the lowest fruit weight was in Illam Selection (59.4 gm). Analysis of variance for different characters showed a high degree of variation among the genotypes. The variability in morphological characters generated valuable information which could be used for a choice of parents for guava breeding programs in the future.

Black guava (Psidium guajava L.): Morphological, biochemical and molecular characterization for pulp colour

Guava is known as “Super fruit”; it is the third richest source of Vitamin C. In this study Black guava is characterized morphologically, biochemically and on molecular basis. Result revealed that Black guava had the maximum total anthocyan in content (9.663 mg/100g) compared to white and pink pulped counterparts. Pink pulped Hisar Surkha and Lalit genotypes contained both lycopene and anthocyanin while another pink pulped genotype, Punjab Pink, had only lycopene. Further, all the eight guava genotypes irrespective of their pulp colour had total carotenoids (0.203 mg/100g - 0.730 mg/100g). Based on our results, the Black guava had unique morphological features like leaf colour, shoot colour and fruit pulp colour. The pulp colour of Black guava is due to the presence of anthocyanins. In general, the pulp colour of guava is due to combinations of more than one pigment and the final colour depends on the relative proportion of those pigments and suggests that “pigments in proportions” explains the pulp colour in guava. Anthocyanin pathway study in Black guava revealed that the primers for DFR and CHS gene of anthocyanin pathway amplified in Punjab Pink and not in case of Black guava.

Black guava (Psidium guajava L.): Morphological, biochemical and molecular characterization for pulp colour

Guava is known as “Super fruit”; it is the third richest source of Vitamin C. In this study Black guava is characterized morphologically, biochemically and on molecular basis. Result revealed that Black guava had the maximum total anthocyan in content (9.663 mg/100g) compared to white and pink pulped counterparts. Pink pulped Hisar Surkha and Lalit genotypes contained both lycopene and anthocyanin while another pink pulped genotype, Punjab Pink, had only lycopene. Further, all the eight guava genotypes irrespective of their pulp colour had total carotenoids (0.203 mg/100g - 0.730 mg/100g). Based on our results, the Black guava had unique morphological features like leaf colour, shoot colour and fruit pulp colour. The pulp colour of Black guava is due to the presence of anthocyanins. In general, the pulp colour of guava is due to combinations of more than one pigment and the final colour depends on the relative proportion of those pigments and suggests that “pigments in proportions” explains the pulp colour in guava. Anthocyanin pathway study in Black guava revealed that the primers for DFR and CHS gene of anthocyanin pathway amplified in Punjab Pink and not in case of Black guava.

Genetic divergence of guava (Psidium guajava L.) genotypes in Bangladesh

A noticeable variation is present among the guava (Psidium guajava L.) genotypes available in Bangladesh. Thirty-three (25 indigenous, 5 released, and 3 exotic) genotypes of guava were used in ex-situ conditions from different locations of Chattagram, Brahmanbaria, Pirojpur, and Gazipur districts and assessed based on 10 traits to know their genetic diversity. The measured traits were number of flowers, fruits, harvested fruits per plant, single fruit weight (g), number of seeds/fruits, thousand seed weight (g), vitamin C, total sugar content, and fruit yield/plant (kg). Twenty-one genotypes showed 100-400 g of single fruit weight, and 12 showed 20-100 g. The genotype G14 (BARI Peyara-1) produced the highest fruit yield/plant (131.04 kg) followed by G24 (PG Muk-005) and G 23 (PG Muk-005) yielded 65.49 kg and 64.62 kg, respectively. Twenty-one genotypes showed above 250 mg/100g vitamin C content. Above 42% (14 genotypes) contained total sugar content of over 5%. The first two axes accounted 58.8% of the total variation among 10 traits. Based on the heatmap analysis, cluster-IV represents a high value containing the number of flowers, fruits, and harvested fruits per plant. The genotypes G 14, G17 (BARI Peyara-4), G21 (PG Sit-003), G23, G24, and G29 (Thai Peyara-3) might be considered the best based on the morpho-biochemical characteristics. Many traits are of significant economic importance and could be used as breeding targets to increase yield and quality. Therefore, variation among guava genotypes will be an excellent source for future crop improvements. SAARC J. Agric., 20(1): 15-28 (2022)

Combined Radiometric Analysis Related to Guava Leaf Phenology in Response to Soil Application of Paclobutrazol (PBZ)

The leaf-response to three-soil applied treatments of Paclobutrazol (PBZ; 1000, 2000 and 0 ppm-control) was studied in a high-density plantation of eight guava (Psidium guajava) genotypes trees. All materials were prunned in vase form, with two to three major branches, yearly prunning for triggering the annual production cycle, and average height of 2.0 m. The dataset comprises fourth radiometric indices highly related to plant physiological activities. The dataset model took into account data collection dates, guava genotypes, and the positional effect of sun radiation on leaves based on their proximity to the canopy level and downward to the base of the woody seasonal-branch. Unexpectedly, there were no significant differences (NS) in PBZ treatments for genotypes, leaf position and radiometric indices. Analysis of the radiometric indices data revealed that anthocyanin (ARI index) and chlorophyll (PRI index) have a strong inverse relationship. Significant differences (P ≤ 0.05) were found between guava genotypes, and anthocyanin content; these results show that guava genotypes have varied responses, which could derive in their classification based-on drought resistance or low water requirements, however, it is important to note that additional research is required to determine the scope of these indications.

Phytochemical Characterization in Relation to Genetic Variability and Heritability Among Guava Genotypes

Phytochemical Characterization in Relation to Genetic Variability and Heritability Among Guava Genotypes

Genetic-molecular characterization in guava full-sib progeny

Brazil is one of the world’s largest producers of guava (Psidium guajava L.), a very promising fruit in the northern region of the state of Rio de Janeiro. Despite this, no guava cultivar has been developed for the region. Thus, this study proposed to examine a population of guava full sibs using microsatellite markers and to identify which genotypes are the most divergent for future crosses, to select cultivars better adapted to the soil and climatic conditions of northern Rio Janeiro. Ninety-six superior genotypes were selected according to their agronomic traits, which were characterized using 45 microsatellite markers. The genetic distance between the analyzed genotypes, their clustering pattern and the genetic structure of the population were estimated. Hierarchical cluster analysis by the neighbor joining method indicated the formation of three distinct groups. The use of molecular information revealed the existence of moderate genetic variability between the genotypes of the full-sib families. Bayesian analysis separated the genotypes into only two groups, as the individuals shared most of the analyzed genomic regions. The most genetically divergent guava genotypes, that is, those allocated to different groups, such as genotypes 5 and 85, should be recommended for future crosses to obtain segregating populations, thus giving continuity to the guava breeding program.

Assessment of morpho-genetic diversity of guava (Psidium guajava) hybrids and genotypes

A total of 20 diverse guava genotypes, including the newly bred hybrids were characterized using the morphological, physio-biochemical parameters and microsatellite markers at ICAR-IARI, New Delhi during 2018-19. Most of the qualitative morphological and physio-biochemical parameters had a coefficient of variation value >20%, which indicated substantial diversity. The longest leaves (14.87 cm) were recorded in Lalit, which was statistically at par with Pant Prabhat (14.67 cm), while amongst the hybrids, it is in GH 2018-10 (13.93 cm). The maximum leaf area was recorded in Pant Prabhat (60.33 cm2) while amongst hybrids it was in GH 2018-2 (53.40 cm2). The highest stomatal conductance and net photosynthetic rate was recorded in guava genotype Shweta (9.63 μmol/m2/s) (0.25 mol/m2/sec) while amongst the hybrids it was in GH 2018-8 (8.73μmol/m2/s) (0.26 mol/m2/sec), respectively. The mean genetic diversity indices, viz. major allelic frequency, number of alleles, gene diversity, heterozygosity and polymorphic information content of eight SSRs were 0.497, 3.75, 0.599, 0.071 and 0.542, respectively among the guava genotypes. Furthermore, the eight SSRs based Neighbour-joining (N-J) tree separated the newly bred guava hybrids into different clusters, clades and out-groups.

GENETIC VARIABILITY IN INBRED GUAVA FAMILIES MEDIATED BY AGRONOMIC TRAITS

The aim of this study was to evaluate the existing diversity among genotypes from inbred guava families obtained from a breeding program. To characterize the 61 genotypes, 51 descriptors were evaluated, including 15 quantitative, 16 qualitative, and 20 seed descriptors obtained digitally using the Graundeye® image analysis system. Based on the quantitative, qualitative, and seed descriptors, the Ward-MLM strategy was employed and was efficient in detecting divergence among guava genotypes using qualitative and quantitative descriptors. The evaluated population has genetic diversity and genotypes with important agronomic traits that allow the continuity of the breeding program with genetic gains. The descriptors that most contributed to divergence among the evaluated guava genotypes were leaf length/width, fruit length, fruit pulp thickness, leaf length, and fruit pulp weight. The seed descriptors obtained by digital image analysis were useful in estimating genetic diversity in guava.

Genotypic and phenotypic diversity in guava (Psidium guajava L.) genotypes from Iran

Genotypic and phenotypic diversity in guava (Psidium guajava L.) genotypes from Iran

Evaluation of Guava (Psidium guajava L.) genotypes for growth and yield in middle Gujarat condition

An experiment was conducted for evaluation of eight different guava genotypes for growth, yield and yield attributes for their suitability under Middle Gujarat conditions. The collected eight different guava cultivars viz., AGRS 1, AGRS 2, AGRS 3, AGRS 4, AGRS 5, AGRS 6, AGRS 7, AGRS 8 and two checks Dholka and Lalit were showed wide range of variation with respect to plant growth, yield and yield attributes of fruit at sub tropics of middle Gujarat conditions. Results of three year study indicated that the red flesh genotype AGRS 8 (35.85 kg/plant) produced higher fruit yield followed by AGRS 4 (32.23 kg/tree). This genotype has lower incidence of fruit fly damage as compared to the checks Lalit and Dholka. The genotype AGRS 8 (Lal Bahadur) is out yielder and suitable for cultivation under middle Gujarat condition. The genotype respond well to mrig-bahar (Jun-July flowering time) to get maximum yeild.

Phenomics approaches: genetic diversity and variance components in a S2 guava family by seed traits

Guava is of great economic importance in Brazil. The development of new cultivars by obtaining inbreeding lines has been a promising option. The objective of this work was to evaluate the S2 families of Psidium guajava using seed attributes. Different characters of physiological quality of guava seeds were studied, in addition to performing digital phenotyping of characteristics of geometry, texture and colors of the seeds. The variables were analyzed simultaneously using the Ward-Modified Location Model (MLM) method and carried out individual analyses of variance for estimating genetic parameters of the population. The formation of more than one group of divergent genotypes was observed, the geometry characteristics were more impacting for the discrimination of the genotypes, a high phenotypic correlation was observed with the germination variables and dry matter weight. High heritabilities were verified for the variables related to seed quality, indicating success in selecting vigorous genotypes. The Ward-MLM method is a useful tool to detect genetic diversity among genotypes of inbred guava. Thus, the most divergent genotypes with high germination potential can be recommended for future crosses or self-fertilized to obtain new lines in the guava breeding program.