Draft Genomes of two Artocarpus plants, Jackfruit (A. heterophyllus) and Breadfruit (A. altilis)

Abstract

Two of the most economically important plants in the Artocarpus genus are jackfruit (A. heterophyllus Lam.) and breadfruit (A. altilis (Parkinson) Fosberg). Both species are long-lived trees that have been cultivated for thousands of years in their native regions. Today they are grown throughout tropical to subtropical areas as an important source of starch and other valuable nutrients. There are hundreds of breadfruit varieties that are native to Oceania, of which the most commonly distributed types are seedless triploids. Jackfruit is likely native to the western Ghats of India and produces one of the largest tree-borne fruit structures (reaching up to 100 pounds). To date, there is limited genomic information for these two economically important species. Here, we generated 273 Gb and 227 Gb of raw data from jackfruit and breadfruit, respectively. The high-quality reads from jackfruit were assembled into 162,440 scaffolds totaling 982 Mb with 35,858 genes. Similarly, the breadfruit reads were assembled into 180,971 scaffolds totaling 833 Mb with 34,010 genes. A total of 2,822 and 2,034 expanded gene families were found in jackfruit and breadfruit, respectively, enriched in pathways including starch-and sucrose metabolism, photosynthesis and others. The copy number of several starch synthesis related genes were found increased in jackfruit and breadfruit compared to closely related species, and the tissue specific expression might imply their sugar-rich and starch-rich characteristics. Overall, the publication of high-quality genomes for jackfruit and breadfruit provides information about their specific composition and the underlying genes involved in sugar and starch metabolism.

Whole-Genome Sequencing of a Year-Round Fruiting Jackfruit Variety Reveals Very High Single Nucleotide Polymorphisms in Inter-Genic Regions

“…2). The estimated size is similar to the recently reported 1.01Gb genome size of A. heterophyllus [5], and is consistent with the c-value of 1.20 pg [27]. The BARI Kanthal-3 has a higher heterozygosity rate compared to the only one available reference genome of a seasonal jackfruit from India recently published by Sahu et al [5].…”

“…The place of origin of this fruit tree is still unclear, but it is predicted to be indigenous to the rainforests of the Western Ghats of India. It is widely cultivated throughout the tropical lowlands in South and Southeast Asia, parts of central and eastern Africa, and Brazil [5][6][7]. Bangladesh is one of the highest jackfruit producing countries in the world.…”

“…Its demand is increasing gradually due to its low price, high nutritious value, diversi ed uses and potentials for commercial cultivation and processing industry [7]. The jackfruit is commonly referred to as "poor man's food" due to its lower market price as well as high abundance in the summer season [5,8]. It is grown all over the Bangladesh, especially profusely in the central terrace ecosystem [9].…”

“…Jackfruit is a highly priority fruit plant in Bangladesh as the National Agricultural Research System (NARS) has recently placed a focus on improving fruiting characteristics of this species and supporting its commercial development. Until now, only a limited amount of genomic information has been made available for the genus of A. heterophyllus [5,25]. Although the development of a year-round fruiting variety BARI Kanthal-3 offers an opportunity for commercial cultivation and processing of the jackfruit, nothing is known about the underlying molecular mechanism of its year-round fruiting characteristics and other bene cial traits.…”

Third-generation sequencing and metabolome analysis reveal candidate genes and metabolites with altered levels in albino jackfruit seedlings

“…The effects of plant albinism on the expression of genes and metabolites Although the draft genome of jackfruit (A. heterophyllus) have been published [19], the results of clean reads mapped to genome were not good as mapped to the full-length transcripts obtained by SMRT sequencing combined with Illumina sequencing (Supplementary Table S1). So we used the full-length transcripts with an average length of 2,723 bp as reference sequences for A. heterophyllus.…”