ABSTRACT
DNA marked-assisted selection of medicinal plants accelerated the breeding and promotion of new cultivars, and guaranteed the healthy development of Chinese medicinal materials industry. The first disease-resistant cultivar of notoginseng, namely "Miaoxiang Kangqi 1", served as the object of study. We evaluated the Kangqi's resistance of seeds, seedlings and root against the pathological bacteria (Fusarum oxysporum) of root rot. Compared to the traditional cultivars, the disease index of notoginseng seeds declined by 52.0% after inoculation for seven days; the death rate of seedlings and disease index of root respectively decreased by 72.1% and 62.4% after inoculation for 25 days. Additionally, the growth inhibition ratio of notoginseng seeds and seedlings declined after inoculation. The seeds, seedlings and roots of "Miaoxiang Kangqi 1" showed significantly resistant to root rot. The evaluation of disease-resistance of Kangqi provided the basis for the popularization of new cultivar and guaranteed the favoring conduct of notoginseng pollution-free cultivation.
ABSTRACT
DNA marker-assisted selection of medicinal plants is based on the DNA polymorphism, selects the DNA sequences related to the phenotypes such as high yields, superior quality, stress-resistance and so on according to the technologies of molecular hybridization, polymerase chain reaction and high-throughput sequencing, and assists the breeding of new cultivars. This study bred the first disease-resistant cultivar of notoginseng "Miaoxiang Kangqi 1" using the technology of DNA marker-assisted selection of medicinal plants and systematic breeding. The disease-resistant cultivar of notoginseng contained 12 special SNPs based on the analysis of Restriction-site Associated DNA Sequencing (RAD-Seq). Among the SNP (record_519688) was related to the root rot-resistant characteristics, which indicated this SNP could serve as genetic markers of disease-resistant cultivars and assist the systematic breeding. Compared to the conventional cultivated cultivars, the incidence rate of root-rot and rust-rot in notoginseng seedlings decreased by 83.6% and 71.8%, respectively. The incidence rate of root-rot respectively declined by 43.6% and 62.9% in notoginseng cultivation for 2 and 3 years compared with those of the conventional cultivated cultivars. Additionally, the potential disease-resistant groups were screened based on the relative SNP, and this model enlarged the target groups and advanced the breeding efficiency. DNA marker-assisted selection of medicinal plants accelerated the breeding and promotion of new cultivars, and guaranteed the healthy development of Chinese medicinal materials industry.
ABSTRACT
A meloidoginose tem sido considerada uma das mais importantes doenças da cultura do tomate. O uso de tomateiros resistentes ao nematoide das galhas é medida bastante utilizada no controle de diferentes espécies, entretanto, a reação de tomateiros à Meloidogyne enterolobii ainda é pouco conhecida. Portanto, objetivou-se a determinação da reprodução de M. enterolobii em dez híbridos de tomate (Absoluto, Cascade, Cordillera, Donatto, Ellen, Fascínio, Laura, Marguerita, Nícolas e Sanni) e dois genótipos experimentais (05 tom0041 e 08 tom00345). Os ensaios foram conduzidos em casa de vegetação e em BOD (25°C), com cinco e três repetições por tratamento, respectivamente. A infestação do substrato foi realizada com 5.000 ovos e eventuais juvenis de segundo estádio de M. enterolobii/vaso, dois dias após o transplante das plântulas. A avaliação do índice de galhas, índice de massa de ovos, população final e fator de reprodução foi realizada 60 dias após a inoculação. Em ambos os ensaios, verificou-se a suscetibilidade de todos os genótipos e híbridos avaliados.
The diseases caused by root-knot nematodes on tomato have been considered as the most dangerous for this crop. This research aimed to study the reaction of ten tomato hybrids (Absoluto, Cascade, Cordillera, Donatto, Ellen, Fascínio, Laura, Marguerita, Nícolas and Sanni) and two genotypes (05 tom0041 and 08 tom00345) to M. enterolobii. The experiments were developed out separately in a greenhouse and BOD (25°C). The substrate inoculation was made with 5,000 eggs and second stage juveniles of M. enterolobii. The variables gall and egg mass indexes, final population and the reproduction factor were determined 60 days after inoculation. On both experiments, all the genotypes and hybrids were susceptible to M. enterolobii.