Breeding Walnuts (Juglans Regia)

McGranahan, Gale H.; Leslie, Chuck

doi:10.1007/978-0-387-71203-1_8

Cited by 42 publications

(28 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Number of nuts per inflorescence (1-3) was found similar with checks (Table 3). These results are in line with previous studies (McGranahan and Leslie, 1991;Akca and Ozongun, 2004). The tree vigour was high with spreading growth habit having side branches spreading upward without competing with central leader (Table 3; Figure 1D and 1E).…”

Section: Yield Quantificationsupporting

confidence: 92%

“…In comparison to check varieties, CITH-W-121 had short trapezoid nut shape, light shell with medium texture, complete shell integrity, intermediate shell seal and shell strength. Yield potential in walnut depends on bearing habit, number of fruit on terminal and lateral shoots, lateral fruitfulness, nut weight, kernel ratio, and nut size (McGranahan and Leslie, 1991;Akca and Ozongun, 2004)…”

Section: Yield Quantificationmentioning

confidence: 99%

“…The bearing habit also influences tree structure and affects the productivity (Laurens et al, 2000). The lateral bearing is associated with precocity (Serr, 1962;Forde, 1979) and higher yield (McGranahan and Leslie, 1991;Solar et al, 2001). The lateral bud fruitfulness is considered as a most significant yield factor, which can also be manipulated through breeding (Akca and Ozongun, 2004).…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Lateral Bearing Trait in Indian Walnut (Juglans regia L.) Germplasm: a Potential Yield Contributing Trait in Early Age of the Tree

Chand¹,

Kashmir²,

Singh³

et al. 2017

IJBSM

View full text Add to dashboard Cite

The present study was carried out during year 2015 and 2016 at ICAR-Central Institute of Temperate Horticulture (CITH), Srinagar, India with the objective of trait specific characterization of walnut accessions with specific emphasis on lateral bearing trait. The study was initiated on pre-selected indigenous accessions collected from various pockets of North Western Himalaya and maintained at field gene bank of the institute. The most widely grown varieties 'Sulaiman' and 'Hamdan' were used as local check. All the accessions were monitored to identify the bearing habit. Only one accession CITH-W-121 (IC-0622836) was found with lateral bearing trait, which had fruit bearing on leafy shoots emerging from terminal, sub terminal as well as from lateral buds of 1-year-old shoot. Bearing on lateral leafy shoots developing from lateral buds of 1-year-old shoot is being reported for the first time in indigenous genetic resources of walnut which is an important trait to improve productivity. Lateral leafy shoots emerged all along 1-year old shoot, in which about 50% lateral leafy shoots bearing 1−3 fruits panicle-1. Overall 40−60% lateral leafy shoots in a tree were bearing fruits in this accession. In term of yield, CITH-W-121 (11.07 kg tree-1) was found significantly superior to Sulaiman (5.85 kg tree-1) and Hamdan (5.48 kg tree-1). Yield efficiency was recorded significantly higher in CITH-W-121 (26.37 g cm-2 tcsa) over the two ruling check varieties i.e, Hamdan (13.99 g cm-2 tcsa) and Sulaiman (9.65 g cm-2 tcsa). In accession CITH-W-121, nut weight and kernel weight was recorded on par with Hamdan, while kernel recovery was on par with Sulaiman. This accession has desirable traits like well filled, plump and light coloured kernel with moderately easy removal of kernel halves and is having a good balance between vegetative growth and fruit bearing.

show abstract

Section: Yield Quantificationsupporting

confidence: 92%

Section: Yield Quantificationmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Lateral Bearing Trait in Indian Walnut (Juglans regia L.) Germplasm: a Potential Yield Contributing Trait in Early Age of the Tree

Chand¹,

Kashmir²,

Singh³

et al. 2017

IJBSM

View full text Add to dashboard Cite

show abstract

“…Persian walnut (Juglans regia L.) is one of the oldest food sources known (Aradhya et al, 2006) and is subject to myths and legends since ancient times (Rondeau, 1997). It is a tree species with 2n = 2x = 32 chromosomes (Woodworth, 1930), growing in temperate region (McGranahan and Leslie, 2009). Walnut is an important tree crop in France after apple, with a worldwide inshell walnut production led by China, California, and Iran 1 .…”

Section: Introductionmentioning

confidence: 99%

Genome-Wide Association Study Reveals Candidate Genes Involved in Fruit Trait Variation in Persian Walnut (Juglans regia L.)

et al. 2021

View full text Add to dashboard Cite

Elucidating the genetic determinants of fruit quality traits in walnut is essential to breed new cultivars meeting the producers and consumers’ needs. We conducted a genome-wide association study (GWAS) using multi-locus models in a panel of 170 accessions of Juglans regia from the INRAE walnut germplasm collection, previously genotyped using the AxiomTMJ. regia 700K SNP array. We phenotyped the panel for 25 fruit traits related to morphometrics, shape, volume, weight, ease of cracking, and nutritional composition. We found more than 60 marker-trait associations (MTAs), including a highly significant SNP associated with nut face diameter, nut volume and kernel volume on chromosome 14, and 5 additional associations were detected for walnut weight. We proposed several candidate genes involved in nut characteristics, such as a gene coding for a beta-galactosidase linked to several size-related traits and known to be involved in fruit development in other species. We also confirmed associations on chromosomes 5 and 11 with nut suture strength, recently reported by the University of California, Davis. Our results enhance knowledge of the genetic control of important agronomic traits related to fruit quality in walnut, and pave the way for the development of molecular markers for future assisted selection.

show abstract

“…Juglans microcarpa , also called Texas black walnut, grows in isolated, favorable riparian habitats in the arid plains of the United States and northern Mexico. Although it is more a shrub than a tree, it has value in rootstock breeding as well ( McGranahan and Leslie 2009 ). J. sigillata is a medium-sized tree found on mountain slopes in southern China and in Tibet ( Brach and Song 2006 ).…”

mentioning

confidence: 99%

Genomic Variation Among and Within SixJuglansSpecies

Stevens¹,

Woeste

Chakraborty

et al. 2018

G3 Genes|Genomes|Genetics

View full text Add to dashboard Cite

Genomic analysis in Juglans (walnuts) is expected to transform the breeding and agricultural production of both nuts and lumber. To that end, we report here the determination of reference sequences for six additional relatives of Juglans regia: Juglans sigillata (also from section Dioscaryon), Juglans nigra, Juglans microcarpa, Juglans hindsii (from section Rhysocaryon), Juglans cathayensis (from section Cardiocaryon), and the closely related Pterocarya stenoptera. While these are ‘draft’ genomes, ranging in size between 640Mbp and 990Mbp, their contiguities and accuracies can support powerful annotations of genomic variation that are often the foundation of new avenues of research and breeding. We annotated nucleotide divergence and synteny by creating complete pairwise alignments of each reference genome to the remaining six. In addition, we have re-sequenced a sample of accessions from four Juglans species (including regia). The variation discovered in these surveys comprises a critical resource for experimentation and breeding, as well as a solid complementary annotation. To demonstrate the potential of these resources the structural and sequence variation in and around the polyphenol oxidase loci, PPO1 and PPO2 were investigated. As reported for other seed crops variation in this gene is implicated in the domestication of walnuts. The apparently Juglandaceae specific PPO1 duplicate shows accelerated divergence and an excess of amino acid replacement on the lineage leading to accessions of the domesticated nut crop species, Juglans regia and sigillata.

show abstract

Breeding Walnuts (Juglans Regia)

Cited by 42 publications

References 25 publications

Lateral Bearing Trait in Indian Walnut (Juglans regia L.) Germplasm: a Potential Yield Contributing Trait in Early Age of the Tree

Lateral Bearing Trait in Indian Walnut (Juglans regia L.) Germplasm: a Potential Yield Contributing Trait in Early Age of the Tree

Genome-Wide Association Study Reveals Candidate Genes Involved in Fruit Trait Variation in Persian Walnut (Juglans regia L.)

Genomic Variation Among and Within SixJuglansSpecies

Contact Info

Product

Resources

About