Appendix I: Variables/parameters of rice brown planthopper (BPH) mechanistic population simulation model
Variable/parameter name / Definition / Variable equations/parameter values
A.Variables (calculated as per the following equations)
AD / Total number of adults / AD= INTGRL (IAD, RAD)
ADMO / Adult death rate (No./day) / ADMO= AD*ETAD/TTAD+ (ADR* ADPRE)
ADR / Adult formation rate (No./day) / ADR= NL*ETNL/TTNL
EG / Total number of eggs / EG= INTGRL (IEG, REG)
EGMO / Egg mortality rate (No./day) / EGMO= INFR+EGPAR+EGPRE+ (1.-TSUEG)
EGR / Egg laying rate (No./day) / EGR= AD*SRAT*FECND
ETAD / Effective temperature for adults (oC) / ET AD = (TPAV-TDAD)*AFGEN (TCORC, TPAV)
ETEG / Effective temperature for eggs (oC) / ETEG = (TPAV-TDEG)*AFGEN (TCORC, TPAV)
ETNS / Effective temperaure for small nymphs (oC) / ETNS = (TPAV-TD NS)*AFGEN (TCORC, TPAV)
ETNL / Effective temepraure for large nymphs (oC) / ETNL = (TPAV-TD NL)*AFGEN (TCORC, TPAV)
IEG / Initial number of eggs / 0 (Model was initialized with adult stage and therefore initial values for other stages were set to zero
INL / Initial number of large nymphs
INS / Initial number of small nymphs
NLV / Rate of available nitrogen in leaves (kg/ha/day) / NLV = NALV -SUKNLV
NST / Rate of available nitrogen in stems (kg/ha/day) / NST = NA ST-SUKNST
NL / Total number of large nymphs / NL= INTGRL (INL, RNL)
NLMO / Large nymph mortality Rate (No./day) / NLMO= NLPAR+NLPRE+ (1-TSURNL)
NLR / Rate of conversion of small nymph to large nymphs (No./day) / NLR= NS*ETNS/TTNS
NS / Total number of small nymphs / NS= INTGRL (INS, RNS)
NSMO / Small nymph mortality rate (No./day) / NSMO= NSPAR+NSPRE+(1.-TSURNS)
NSR / Rate of formation of small nymph from eggs (No./day) / NSR= EG* ETEG/TTEG
ADR / Adult formation rate / ADR=NL*ETNL/TTNL
PPOSK / BPH population on the crop (No./ha) / PPOSK=NS+NL+AD
RAD / Rate of change of adults (No./day) / RAD= ADR-ADMO
REG / Rate of change of eggs (No./day) / REG= EGR-REGLO-NSR
REGLO / Egg loss rate (No./day) / REGLO= EGR*EGMO
RNL / Rate of change of large nymphs (No./day) / RNL= NLR-RNLLO-ADR
RNLLO / Large nymph loss rate (No./day) / RNLLO= NLR*NLMO
RNS / Rate of change of small nymphs (No./day) / RNS= NSR-RNSLO-NLR
RNSLO / Small nymph loss rate (No./day) / RNSLO= NSR*NSMO
SUCKLV / Assimilate sucking rate of BPH on leaves reserves (kg/ha/day) / SUCKLV = SUCKRT*PPOSK*SKINWT*FRPPOLV
SUCKST / Assimilate sucking rate of BPH on stem reserves (kg/ha/day) / SUCKST = SUCKRT*PPOSK*SKINWT*FRPPOST
SUKNLV / Nitrogen sucking rate of BPH on leaves (kg/ha/day) / SUKNLV,=SUKNRT*PPOSK*SKINWT*FRPOLV
SUKNST / Nitrogen sucking rate of BPH on stem (kg/ha/day) / SUKNST=SUKNRT*PPOSK*SKINWT*FRPOST
TCORC / Correction factor for non-linear response in thermal time / Calculated as function of TPAV, 18-30oC being optimum
TPAV / Daily average temperature (oC) / Taken from weather file
TSUEG / Adverse effect of temperature on egg survival (%) / Calculated as function of TPAV, 18-30oC being optimum(Pathak, 1968; Krishnaiah et al., 2006)
TSURNL / Adverse effect of temperature on nymphal survival (%) / Calculated as function of TPAV, 18-30oC being optimum(Pathak, 1968; Krishnaiah et al., 2006)
TSURNS / Adverse effect of temperature on nymphal survival (%) / Calculated as function of TPAV, 18-30oC being optimum(Pathak, 1968; Krishnaiah et al., 2006)
B. Parameters
IAD / Initial number of adults / 100
EGPAR / Egg parasitism / 0.3 % (Ho and Liu, 1969)
EGPRE / Egg predation (%) / 0.0 %
FECND / Number of eggs laid per day per female / 100 per day( Heong ,1982)
INFR / Infertile eggs / 0.26 % (Bentur and Kalode, 1985)
NLPRE / Large nymphal predation / 0.5 %(Cook and Perfect, 1985).
NLPAR / Large nymphal parasitism (%) / 0.1% (Ho and Liu,1969 & Holt et al., 1987)
NSPAR / Small nymphal parasitism / 0.15 %(Ho and Liu, 1969 & Holt et al., 1987)
NSPRE / Small nymph predation / 0.15 %(Holt et al., 1987)
ADPRE / Adult predation (%) / 0.0%
SKINWT / Weight of one planthopper / 2.0 mg (Sujithra et al., 2011)
SRAT / Proportion of females in the population / 0.5(Holt et al., 1987)
SUCKRT / Assimilate sucking rate per unit insect weight / 2.01E-6 kg/mg insect weight/day
(Sujithra et al., 2011)
SUKNRT / Nitrogen sucking rate per unit insect weight / 4.02E-8 kg/ mg insect weight/day
(Sujithra et al., 2011)
TDAD / Development threshold for adults / 9.6 Degree days (DD)
TDEG / Development threshold for eggs / 10.4 DD(Bae et al., 1987; Krishnaiah et al., 2005)
TDNL / Development threshold for large nymphs / 9. 5 DD
TDNS / Development threshold for small nymphs / 8. 8 DD
TTAD / Thermal constant for adults / 161 DD
TTEG / Thermal constant in degree-days for eggs / 138 DD(Bae et al., 1987; Krishnaiah et al., 2005)
TTNL / Thermal constant for large nymphs / 140 DD
TTNS / Thermal constant for small nymphs / 126 DD