A method of determining cut position of automatic stem removal system for salted wakame

In the wakame manufacturing procedure, the manual operation process of stem removal is known to hinder the production process. In order to solve this problem, the manufacture aspires to develop an automatic wakame stem removal system. The purpose of this paper is to propose a cut position detection method for the system by picking up the characteristic changes that appear at the cross section of the wakame. In this method, with the utilization of exposure control, two images are captured from the same cross section that is made by a developed device. These images are used in the segmentation of the cross section. The positions where the stem should be cut can then be determined through the examination of the thickness of the cross section. To test the performance of the proposed method, 100 cross sections were generated from the roots of 10 samples of the salt-preserved wakame with an interval of 20 mm. In the experiments, the proposed method gave good results to find the cut positions except some misdetection. The experimental results showed that this method is effective and usable to the automatic stem removal system

Genome analyses reveal the hybrid origin of the staple crop white Guinea yam (Dioscorea rotundata)

西アフリカの主食作物ギニアヤムの起源を解明 --ギニアヤムはサバンナと熱帯雨林に生育する野生種の雑種起源--. 京都大学プレスリリース. 2020-12-11.White Guinea yam (Dioscorea rotundata) is an important staple tuber crop in West Africa. However, its origin remains unclear. In this study, we resequenced 336 accessions of white Guinea yam and compared them with the sequences of wild Dioscorea species using an improved reference genome sequence of D. rotundata. In contrast to a previous study suggesting that D. rotundata originated from a subgroup of Dioscorea praehensilis, our results suggest a hybrid origin of white Guinea yam from crosses between the wild rainforest species D. praehensilis and the savannah-adapted species Dioscorea abyssinica. We identified a greater genomic contribution from D. abyssinica in the sex chromosome of Guinea yam and extensive introgression around the SWEETIE gene. Our findings point to a complex domestication scenario for Guinea yam and highlight the importance of wild species as gene donors for improving this crop through molecular breeding

Disentangling the complex gene interaction networks between rice and the blast fungus identifies a new pathogen effector

Studies focused solely on single organisms can fail to identify the networks underlying host–pathogen gene-for-gene interactions. Here, we integrate genetic analyses of rice (Oryza sativa, host) and rice blast fungus (Magnaporthe oryzae, pathogen) and uncover a new pathogen recognition specificity of the rice nucleotide-binding domain and leucine-rich repeat protein (NLR) immune receptor Pik, which mediates resistance to M. oryzae expressing the avirulence effector gene AVR-Pik. Rice Piks-1, encoded by an allele of Pik-1, recognizes a previously unidentified effector encoded by the M. oryzae avirulence gene AVR-Mgk1, which is found on a mini-chromosome. AVR-Mgk1 has no sequence similarity to known AVR-Pik effectors and is prone to deletion from the mini-chromosome mediated by repeated Inago2 retrotransposon sequences. AVR-Mgk1 is detected by Piks-1 and by other Pik-1 alleles known to recognize AVR-Pik effectors; recognition is mediated by AVR-Mgk1 binding to the integrated heavy metal-associated (HMA) domain of Piks-1 and other Pik-1 alleles. Our findings highlight how complex gene-for-gene interaction networks can be disentangled by applying forward genetics approaches simultaneously to the host and pathogen. We demonstrate dynamic coevolution between an NLR integrated domain and multiple families of effector proteins