Resistance To Pokkah Boeng Disease In New And Main Cultivated Sugarcane Varieties

Pokkah boeng is an epidemic fungal disease that seriously affects development of the sugarcane industry in China. Resistance to pokkah boeng disease differs among sugarcane varieties. Breeding and planting resistant cultivars is the most economic and effective measure for controlling this disease. In this study, new sugarcane varieties bred by the China Sugarcane System and the main varieties cultivated in various sugarcane areas, were screened to find new elite pokkah boeng resistant varieties for application in sugarcane production. The natural field resistance to pokkah boeng disease of 60 new varieties was evaluated in regionalized experiment. Meanwhile, the field resistance of the 31 main cultivated varieties was analyzed in Lincang city, Puer city, Yuxi city, Yunnan Province, and in Yizhou district, Guangxi Province, where the incidence of pokkah boeng is particularly high. Field surveys showed that 35 (58.33%) of the 60 new sugarcane varieties were highly resistant to moderately resistant, and 25 (41.67%) were susceptible to highly susceptible. Of the 31 main cultivated varieties, 15 (48.39%) were highly resistant to moderately resistant, and 16 (51.61%) were susceptible to highly susceptible. The results suggested that, in wetter and rainy sugarcane areas with high incidence of pokkah boeng disease, it is necessary to increase efforts to eliminate the susceptible main cultivated varieties and promote the application of resistant new varieties. This will help to achieve a reasonable distribution of varieties, fundamentally control the outbreak of pokkah boeng disease, and facilitate the high-quality development of the sugarcane industry in China.

Effect and Compatibility of Phosphite with Trichoderma sp. Isolates in the Control of the Fusarium Species Complex Causing Pokkah Boeng in Sugarcane

Sugarcane, a highly productive crop, is frequently challenged by different biotic agents, such as the pokkah boeng disease that can cause drastic yield losses of up to 40%. This airborne fungal disease is caused by various Fusarium species integrated into a complex. Integrating novel compounds and biological control agents is of paramount importance to cope with these fungi in sustainable systems. In this study, we aimed to evaluate the effect and compatibility of phosphite (Phi) and Trichoderma sp. in the control of Fusarium sp., in vitro and in planta. Using in vitro tests, we evaluated the effects of Phi (0, 500, 1000, 2000, 4000, and 8000 µg mL−1) and the compatibility of Phi + Trichoderma (isolates Taz 001, 013, and 016) on the pathogen complex. Using in planta tests, we evaluated the compatibility of Phi + Trichoderma (Taz-016) in the control of Fusarium in sugarcane plants under greenhouse conditions. A synergistic effect of Phi + Trichoderma was observed in vitro on the control of the pathogen, especially when combining 1000 µg mL−1 + Trichoderma Taz-016. In the in planta trial, combining 4000 µg mL−1 Phi + Trichoderma Taz-016 showed the best control of Fusarium infection, improving plant height, culm length and leaf dry weight.

High-Quality Genome Sequence Resource for Fusarium andiyazi Causing Pokkah Boeng Disease of Sugarcane in China

Sugarcane pokkah boeng disease (PBD) is emerging as a prevalent foliar disease in China. This airborne disease is caused by the Fusarium species complex. To investigate the diversity and evolution of Fusarium species, we performed the whole-genome sequencing of Fusarium andiyazi YN28 using a combination of the Oxford Nanopore and the Illumina technology. The F. andiyazi YN28 genome was sequenced, assembled, and annotated. A high-quality genome was assembled into 24 contigs with an N50 of 2.80 Mb. The genome assembly generated a total size of 44.1 Mb with a GC content of 47.64%. A total of 15,508 genes were predicted, including 794 genes related to the carbohydrate-active enzymes, 397 ncRNAs, 155 genes associated with transporter classification, 4,550 genes linked to pathogen-host interactions, and 269 genes involved in effector proteins. Collectively, our results will provide insight into the host-pathogen interaction and will facilitate the breeding of new varieties of sugarcane resistant to PBD.

Evaluation of Promising Sugarcane Clones in Plant Cane against Natural Infection of Pokkah Boeng Disease

Pokkah boeng caused by Fusarium sp is becoming a serious fungal disease on basis of its rapid spread during last few years, posing new threat to sugarcane cultivation. Earlier Pokkah boeng disease was of minor importance but now it has become matter of concern as it is spreading rapidly in sugarcane growing areas having monoculture of single variety. The present investigation entitled “Evaluation of promising sugarcane clones in plant cane against natural infection of pokkah boeng disease” was carried out at Regional Sugarcane and Rice Research station, Rudrur, Nizamabad, Telangana (India) to identify the source of resistance with single series design. Among the ten promising sugarcane clones evaluated in plant cane against Pokkah boeng disease three clones viz., 2014R11, 2010R854 and 83R23 showed resistant reaction.