Gene mapping of bruchid resistance in moth bean (Vigna aconitifolia)

概要


ሗ࿌␒ྕ

ͤ   ➨  ྕ




୺ ㄽ ᩥ ࡢ せ ᪨


Gene



aconitifolia)
 ㄽᩥ㢟┠

mapping

of

bruchid

resistance

in

moth

(Vigna

㸦 ࣔ ࢫ ࣅ ࣮ ࣥ㸦 Vigna aconitifolia㸧࡟ ࠾ ࡅ ࡿ ࣐ ࣓ ࢰ ࢘ ࣒ ࢩ ᢬ ᢠ ᛶ



ࡢ㑇ఏᏊ࣐ࢵࣆࣥࢢ㸧



RATHNAYAKA GAMAGE Shyali Iroshani
㸦 㺵㺚㺣㺲㺗 㺔㺼㺭㺗㺼 㺚㺊㺲㺶 㺐㺹㺚㺊㺤㸧

 Ặ  ྡ 

bean




ㄽᩥෆᐜࡢせ᪨ 


Bruchids are pests that infest stored grain and cause significant seed loss in legume
crops. Previous research using an F 2 population (F 2 OA) resulting from the cross
between wild moth-bean (Vigna aconitifolia [Jacq.] Mar´echal) accession TN67
(resistant) and cultivated moth-bean accession ICPMO056 (susceptible) showed
that resistance to the azuki bean weevil (Callosobruchus chinensis L.) in TN67 was
due to a single gene located in the major quantitative trait locus called qVacBrc2.1.
In this study, we finely mapped qVacBrc2.1 and identified candidate genes in this
locus using both F 2 OA and a large F 2 population (F 2 NB) derived from the same
cross. In contrast to the previous study, we found that resistance to the pest was
controlled by two genes in the F 2 NB population. Additionally, we added new
markers to qVacBrc2.1 and reanalyzed the QTL in the F 2 OA population, which
revealed that qVacBrc2.1 was composed of two linked QTLs, qVacBrc2.1-A and
qVacBrc2.1-B. We verified the presence of qVacBrc2.1-B using the F 2 NB
population. Comparative genomics using three Vigna spp. strongly suggested the
presence of two tandemly duplicated genes, VacPGIP1 and VacPGIP2, which

encoded polygalacturonase inhibitors (polygalacturonase-inhibiting proteins) and
were candidates for conferring resistance. However, only VacPGIP1 was
successfully cloned and sequenced. The comparison of VacPGIP1 coding sequences
of TN67 and ICPMO056 showed eight single nucleotide polymorphisms, three of
which

altered

the

amino-acid

sequence

of

the

predicted

domains

of

polygalacturonase inhibitors in ICPMO056. These findings indicate that VacPGIP1
and VacPGIP2 regulated C. chinensis resistance in TN67. Furthermore, we used
comparative RNA-seq-based transcriptomic analysis to identify candidate genes by
performing RNA-seq of immature and semi-mature seeds from both cultivars. The
study conducted RNA sequencing on immature and semi-mature seeds of two
different cultivars. The results showed that the genes responsible for producing
polygalacturonate inhibitors and lectins had varying levels of expression. Both
stages showed an increase in expression, with a greater increase observed in the
mature stage. This suggests that mature seeds contain a higher concentration of
these proteins, which are important for bruchid resistance in moth bean. The
findings were confirmed by RT-qPCR analysis. In conclusion, the genes responsible
for polygalacturonate inhibitors and lectins are crucial for bruchid resistance in
moth bean.