Honey bees are crucial pollinators for agricultural and natural ecosystems, but are experiencing heavy mortality in Korea due to a complex suite of factors. Extreme winter losses of honey bee colonies are a major threat to beekeeping but the combinations of factors underlying colony loss remain debatable. Finding solutions involves knowing the factors associated with high loss rates. To investigate whether loss rates are related to Varroa control and climate condition, we surveyed beekeepers in korea after wintering (2021–2022 to 2022–2023). The results show an average colony loss rate of 46%(2022) and 17%(2023), but over 40% colony loss before wintering at 2022. Beekeepers attempt to manage their honey bee colonies in ways that optimize colony health. Disentangling the impact of management from other variables affecting colony health is complicated by the diversity of practices used and difficulties handling typically complex and incomplete observational datasets. We propose a method to 1) Varroa mite population Control by several methods , and 2) Many nursing bee put in hive before wintering.
본 연구는 칼랑코에(Kalanchoe blossfeldiana) ‘Discodip’ 의 출하 후 토양수분이 분화품질 및 수명에 미치는 형태적·생리적 영향을 알아보고자 수행되었다. 분화 토양수분 처리는 고습(80% 이상)과 저습(40% 이하)으로 하였고, 분화수명, 분 화수명 종료 증상과 형태적 요인인 지상부와 지하부 생체중 및 건물중, 개화된 꽃 수, 출하 시 대비 개화율을 조사하였고, 생리적 요인은 잎의 엽록소함량 및 엽록소형광(Fv/Fm), 기공크 기 변화율을 분석하였다. 분화수명은 토양 고습 처리구(28.3 일)가 토양 저습 처리구(27.4일)보다 0.9일 높았으나 유의차 는 없었다. 분화수명 종료시점인 출하 4주 후 지하부 생체중 과 건물중, 개화된 꽃 수, 출하 대비 개화율은 토양 고습 처리 구에서 저습 처리구보다 높았다. 잎의 엽록소함량 및 엽록소 형광, 기공크기 변화율은 출하 4주 후 토양 고습 처리구에서 저습 처리구보다 수치적으로 높았으나 유의차는 없었다. 따라 서 출하 후 토양 수분에 따라 분화 칼랑코에의 품질이 시간이 경과될수록 차이가 났으며, 토양수분이 칼랑코에의 분화 품질 에 미치는 중요한 요인이라는 것을 알 수 있었다.
The Riptortus (stinkbug) has a specialized symbiotic organ, M4 midgut, to harboring symbiont Burkholderia. M4 midgut is located in abdomen and surrounded with insect hemolymph. Recently our group demonstrated that symbiotic Burkholderia showed different physiology after adapting in M4 gut compare with in vitro cultured Burkholderia. And population of symbiotic Burkholderia in the M4 midgut is regulated by special organ. However, the molecular mechanism to prevent spreading and migrating symbiont bacteria to other host tissues from symbiotic organ is not clear. Therefore, we assumed that symbiont Burkholderia are susceptible to host humoral immunity after established infection in M4 midgut to prevent spreading and migrating into the other host tissues through Riptortus hemolymph.
To prove this assuming, we tested the susceptibility and survival rate of symbiont Burkholderia in hemolymph of Riptortus in vitro and in vivo. We also examined the susceptibility of symbiont Burkholderia using purified antimicrobial peptides (AMP), pyrrhocoricin-like, thanatin-like and defensin-like AMPs. Finally, we tested inducing ability for AMPs by systemic infection of symbiotic Burkholderia. Gene expression of purified AMPs was not different after systemic infection of both symbiont and in vitro cultured Burkholderia. Surprisingly, in vitro cultured Burkholderia resisted on bacteria injected hemolymph and purified AMPs but symbiont Burkholderia were highly susceptible in bacteria injected hemolymph and purified AMP. These results suggest that symbiont Burkholderia can't survive in the hemolymph after escaping symbiotic organ. Moreover, humoral immunity of host Riptortus is important to prevent spreading and migrating symbiont Burkholderia into the other host tissue or organ from symbiotic organ.