Manufacturing enterprises, manufacturing services and customer constitute the service-oriented manufacturing dynamic network (SMN). The quality of SMN mainly depends on the service module provider. Under the condition of information asymmetry in the market, service module provider pursuits for self-interest maximization, may take quality speculation. Based on the reputation incentive theory, this paper establishes an optimal SMN node quality behavior dynamic model of the contract which combines with dominant incentive mechanism and reputation incentive mechanism, discusses the factors which influence the service module provider's effort level, the conditions of realizing effective reputation incentive and the ways to improve reputation incentive effect.

Tobacco (Nicotiana tabacum L.), one of the chief commercial crops, is wildly cultivated worldwide. In June 2020 and 2021, an unknown bacterial leaf spot on tobacco was found in Hezhou and Hechi City, Guangxi, China. 30% of the tobacco were affected and the rate of diseased leaves reached about 10% in the field under high temperature and rainstorm. The disease mainly damaged the middle and top leaves of tobacco plants at vigorous growing stage. The initial symptoms were water-soaked spots on the frontal half of a leaf, and then expanded into circular to irregular spots with a yellow halo at the edge. The spots mostly appeared dark brown at high air humidity, while yellow brown at low humidity and exhibited a concentric pattern. In severe cases, the lesions coalesced and the whole leaf was densely covered with lesions, resulting in the loss of baking value. A bacterium was consistently isolated from diseased leaf tissues on nutrient agar (NA). Growth on NA was predominantly grayish white circular bacterial colonies with smooth margins, and the bacterium is rod-shaped, gram-negative and fluorescent on King’s B medium. Seven isolates (ND04A-ND04C and ZSXF02-ZSXF05) were selected for molecular identification and pathogenicity tests. Genomic DNA of the bacterium was extracted and the housekeeping gene of cts (encoding citrate synthase) was amplified with the primers cts-Fs/cts-Rs (forward primer cts-Fs: 5’-CCCGTCGAGCTGCCAATWCTGA-3’; reverse primer cts-Rs: 5’-ATCTCGCACGGSGTRTTGAACATC-3’) (Berge et al. 2014; Sarkar et al. 2004). 409-bp cts gene sequences were deposited in the GenBank database for seven isolates (accession no. OK105110-OK105116). Sequence of seven isolates shared 100% identity with several Pseudomonas cichorii strains within the GenBank database (accession no. KY940268 and KY940271), and the phylogenetic tree of cts genes of the seven isolates clustered with the phylogroup 11 of Pseudomonas syringae (accession no. KJ877799 and KJ878111), which was classified as P.cichorii. To satisfy Koch’s postulates, a pathogenicity test was tested by using a needle to dip a suspension of the bacterium (108 CFU/ml) and pricking three holes in the tobacco leaf. The control plants leaves were needled with sterile water. Each tobacco plant was inoculated with three leaves, and the test was repeated three times. All plants were placed in transparent plastic boxes and incubated in a greenhouse at 25 ± 3°C. The water-soaked spots appeared 24h after inoculation and quickly expanded through leaf veins. Three days after inoculation, all the inoculated leaves showed symptoms similar to those observed in the field. Control plants remained healthy. Only P. cichorii was successfully re-isolated from the lesions, confirming Koch’s postulates. Pseudomonas cichorii can infect eggplant, lettuce, tomatoand other crops, and has a wide range of hosts (Timilsina et al. 2017; Ullah et al. 2015). To our knowledge, this is the first report of P. cichorii causing leaf spot on tobacco in China.

Eggplant (Solanum melongena L.) is an economically important vegetable crop in subtropics and tropics. In March 2021, a serious disease on eggplant seedlings about 20 days after transplanting was found in Rong'an County (25°28′ N; 109°53′ E), Guangxi, China, with an incidence of diseased plants of 35%. The initial symptom was water-soaked spots on the leaves, followed by irregular black-brown spots that gradually expanded outward, causing leaf necrosis and defoliation. Even parts of eggplant seedlings died after lesions extended to the stem and the surface of the diseased tissues was covered with white to blue mold. Four diseased eggplants were randomly collected from different fields. Small pieces of the symptomatic tissues were surface sterilized and incubated on potato dextrose agar (PDA) at 28°C for 4 days. A total of 12 strains with similar morphological characteristics were isolated, and four representative strains (FW-01 to FW-04) were characterized. The colony was initially white, changing to yellow-green after 7 days. Phialides were lageniform or ampulliform, 2.9 to 9.75 μm × 1.36 to 4.3 μm (n=50). Conidia were green, ellipsoidal to oblong, smooth, 2.1 to 3.3 μm × 1.6 to 2.33 μm (n=50). Chlamydospores were not observed on PDA. These morphological characteristics are consistent with the description of the genus Trichoderma (Samuels et al. 2012). To confirm the identification, from mycelia of the four isolates and DNA was extracted using the Fungal Genomic DNA Extraction Kit (Bioer Technology [Hangzhou] Co., Ltd.). Three gene regions (ITS, tef1 and rpb2) were amplified (Sadfi-Zouaoui et al. 2009; Atanasova et al. 2010) and sequenced (GenBank Accessions: OL677389 to OL677392 for ITS, OL743178 to OL743181 for tef1 and OL743182 to OL743185 for rpb2). ITS sequences shared 100% identity with sequences of T. reesei (MW514156) and T. parareesei (HM466668), and tef1 and rpb2 sequences showed more than 99% similarity with sequences of T. parareesei (KM263190 and HM182962). The phylogenetic tree of the concatenated sequences showed that four isolates were clustered with T. parareesei. Therefore, the isolates were identified as T. parareesei. To satisfy Koch's postulates, the pathogenicity of four strains was tested on healthy eggplant seedlings planted in a sterile potting mix. Eggplants at four leaves stage were inoculated using conidial suspensions (with a concentration of 1 × 106 conidia/ml), with two leaves of each eggplant inoculated with each isolate and the test repeated three times. The control eggplants leaves were inoculated with sterile water. All plants were placed in a greenhouse at 22 ± 3°C and 85% relative humidity, with a photoperiod of 12 h. The water-soaked spots appeared 48 h after inoculation. All inoculated leaves showed symptoms 3 days post-inoculation. The diseased leaves became brittle and abcissed, while the control leaves remained symptomless. Only T. parareesei was successfully re-isolated from the lesions. Atanasova et al. (2010) found that T. parareesei inhibited the growth of Lepidium sativum seedlings under in vitro conditions (Atanasova et al. 2010). To our knowledge, this is the first report of T. parareesei causing eggplant seedling blight in China. The pathogen can cause substantial economic losses in eggplant production. Therefore, the identification of the pathogen is of great significance for the diagnosis and control of the disease. The results of this study deepen the understanding of the pathogenicity of Trichoderma.